ID Consult

Cold and flu season came early in 2022.

On Nov. 4, 2022, the Centers for Disease Control and Prevention issued a Health Alert Network Health Advisory about early, elevated respiratory disease incidence caused by multiple viruses other than SARS-CoV-2.

Interseasonal spread of respiratory syncytial virus has continued in 2022, with RSV-associated hospitalizations increasing in the late spring and continuing throughout the summer and into the fall. In October, some regions of the country were seeing RSV activity near the peak seasonal levels typically observed in December and January.

Cases of severe respiratory infection in children who tested positive for rhinovirus or enterovirus spiked in August; further testing confirmed the presence of EV-D68 in some children. Rhinovirus and enterovirus continue to circulate and are isolated in hospitalized children with respiratory illness.

In some parts of the country, influenza cases have rapidly increased ahead of what we normally anticipate. According to preliminary estimates from the CDC, between Oct. 1 and Oct. 22, 880,000 people were sickened with flu, 420,000 people visited a health care provider for flu illness, and 6,900 people were hospitalized for flu. The cumulative hospitalization rate is higher than observed at this time of year in every previous flu season since 2010-2011. Hospitalization rates are highest in children aged 0-4 years and adults 65 years and older.

Of course, this report came as no surprise to pediatric health care providers. Many children’s hospitals had been operating at or over capacity for weeks. While a systematic assessment of the surge on children’s hospitals has not been published, anecdotally, hospitals from around the country have described record emergency department visits and inpatient census numbers. Some have set up tents or other temporary facilities to see ambulatory patients and have canceled elective surgeries because of a lack of beds.

There is no quick or easy solution to stem the tide of RSV-related or enterovirus/rhinovirus admissions, but many flu-related hospitalizations are vaccine preventable. Unfortunately, too few children are receiving influenza vaccine. As of the week ending Oct. 15, only about 22.1% of eligible children had been immunized. The American Academy of Pediatrics and the CDC recommend that all children are vaccinated, preferably by the end of October so they have time to develop immunity before influenza starts circulating. As it stands now, the majority of the nation’s children are facing a flu season without the benefits of vaccine.

There is still time to take steps to prevent this flu season from becoming one of the worst in recent memory. A strong provider recommendation for influenza vaccine is consistently associated with higher rates of vaccine acceptance. We need to recommend influenza vaccine to all eligible patients at every visit and in every setting. It will help if we can say it like we mean it. Some of us are tired of debating the merits of COVID-19 vaccine with families and may be leery of additional debates about flu. Some of us may just be tired, as many practices have already expanded office hours to care for the influx of kids with respiratory illness. On the heels of two atypical flu seasons, a few of us may be quietly complacent about the importance of flu vaccines for children.

Anyone in need of a little motivation should check out a paper recently published in Clinical Infectious Diseases that reinforces the value of flu vaccine, even in a year when there is a poor match between the vaccine and circulating viruses.

The 2019-2020 flu season was a bad flu season for children. Two antigenically drifted influenza viruses predominated and cases of influenza soared, resulting in the largest influenza epidemic in children in the United States since 1992. Pediatric Intensive Care Influenza Study investigators used a test-negative design to estimate the effectiveness of influenza vaccine in preventing critical and life-threatening influenza in children during that season. The good news: vaccination reduced the risk of critical influenza by 78% against H1N1pdm09 viruses that were well-matched to vaccine and by 47% against mismatched viruses. Vaccination was estimated to be 75% protective against antigenically drifted B-Victoria viruses. Overall vaccine effectiveness against critical illness from any influenza virus was 63% (95% confidence interval, 38%-78%).

While it might be tempting to attribute suboptimal immunization rates to vaccine hesitancy, ready availability remains an issue for some families. We need to eliminate barriers to access. While the AAP continues to emphasize immunization in the medical home, especially for the youngest infants, the 2022 policy statement suggests that vaccinating children in schools, pharmacies, and other nontraditional settings could improve immunization rates. To the extent feasible, we need to work with partners to support community-based initiatives and promote these to families who struggle to make it into the office.

Improving access is just one potential way to reduce health disparities related to influenza and influenza vaccination. Over 10 influenza seasons, higher rates of influenza-associated hospitalizations and intensive care unit admissions were observed in Black, Hispanic, and American Indian/Alaska Native people. These disparities were highest in children aged younger than 4 years and influenza-associated in-hospital deaths were three- to fourfold higher in Black, Hispanic, and Asian/Pacific Islander children, compared with White children. The reason for the disparities isn’t completely clear but increasing immunization rates may be part of the solution. During the 2020-2021 influenza season, flu immunization rates in Black children (51.6%) were lower than those seen in White (57.4%) and Hispanic children (58.9%).

The AAP’s Recommendations for Prevention and Control of Influenza in Children, 2022–2023, highlight a variety of evidence-based strategies to increase influenza immunization rates. These may provide a little inspiration for clinicians looking to try a new approach. If you wish to share your experience with increasing influenza immunization rates in your practice setting, please email me at Kristina.bryant@louisville.edu.

Dr. Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She is a member of the AAP’s Committee on Infectious Diseases and one of the lead authors of the AAP’s Recommendations for Prevention and Control of Influenza in Children, 2022–2023. The opinions expressed in this article are her own. Dr. Bryant discloses that she has served as an investigator on clinical trials funded by Pfizer, Enanta, and Gilead.

Cold and flu season came early in 2022.

On Nov. 4, 2022, the Centers for Disease Control and Prevention issued a Health Alert Network Health Advisory about early, elevated respiratory disease incidence caused by multiple viruses other than SARS-CoV-2.

Interseasonal spread of respiratory syncytial virus has continued in 2022, with RSV-associated hospitalizations increasing in the late spring and continuing throughout the summer and into the fall. In October, some regions of the country were seeing RSV activity near the peak seasonal levels typically observed in December and January.

Cases of severe respiratory infection in children who tested positive for rhinovirus or enterovirus spiked in August; further testing confirmed the presence of EV-D68 in some children. Rhinovirus and enterovirus continue to circulate and are isolated in hospitalized children with respiratory illness.

In some parts of the country, influenza cases have rapidly increased ahead of what we normally anticipate. According to preliminary estimates from the CDC, between Oct. 1 and Oct. 22, 880,000 people were sickened with flu, 420,000 people visited a health care provider for flu illness, and 6,900 people were hospitalized for flu. The cumulative hospitalization rate is higher than observed at this time of year in every previous flu season since 2010-2011. Hospitalization rates are highest in children aged 0-4 years and adults 65 years and older.

Of course, this report came as no surprise to pediatric health care providers. Many children’s hospitals had been operating at or over capacity for weeks. While a systematic assessment of the surge on children’s hospitals has not been published, anecdotally, hospitals from around the country have described record emergency department visits and inpatient census numbers. Some have set up tents or other temporary facilities to see ambulatory patients and have canceled elective surgeries because of a lack of beds.

There is no quick or easy solution to stem the tide of RSV-related or enterovirus/rhinovirus admissions, but many flu-related hospitalizations are vaccine preventable. Unfortunately, too few children are receiving influenza vaccine. As of the week ending Oct. 15, only about 22.1% of eligible children had been immunized. The American Academy of Pediatrics and the CDC recommend that all children are vaccinated, preferably by the end of October so they have time to develop immunity before influenza starts circulating. As it stands now, the majority of the nation’s children are facing a flu season without the benefits of vaccine.

There is still time to take steps to prevent this flu season from becoming one of the worst in recent memory. A strong provider recommendation for influenza vaccine is consistently associated with higher rates of vaccine acceptance. We need to recommend influenza vaccine to all eligible patients at every visit and in every setting. It will help if we can say it like we mean it. Some of us are tired of debating the merits of COVID-19 vaccine with families and may be leery of additional debates about flu. Some of us may just be tired, as many practices have already expanded office hours to care for the influx of kids with respiratory illness. On the heels of two atypical flu seasons, a few of us may be quietly complacent about the importance of flu vaccines for children.

Anyone in need of a little motivation should check out a paper recently published in Clinical Infectious Diseases that reinforces the value of flu vaccine, even in a year when there is a poor match between the vaccine and circulating viruses.

The 2019-2020 flu season was a bad flu season for children. Two antigenically drifted influenza viruses predominated and cases of influenza soared, resulting in the largest influenza epidemic in children in the United States since 1992. Pediatric Intensive Care Influenza Study investigators used a test-negative design to estimate the effectiveness of influenza vaccine in preventing critical and life-threatening influenza in children during that season. The good news: vaccination reduced the risk of critical influenza by 78% against H1N1pdm09 viruses that were well-matched to vaccine and by 47% against mismatched viruses. Vaccination was estimated to be 75% protective against antigenically drifted B-Victoria viruses. Overall vaccine effectiveness against critical illness from any influenza virus was 63% (95% confidence interval, 38%-78%).

While it might be tempting to attribute suboptimal immunization rates to vaccine hesitancy, ready availability remains an issue for some families. We need to eliminate barriers to access. While the AAP continues to emphasize immunization in the medical home, especially for the youngest infants, the 2022 policy statement suggests that vaccinating children in schools, pharmacies, and other nontraditional settings could improve immunization rates. To the extent feasible, we need to work with partners to support community-based initiatives and promote these to families who struggle to make it into the office.

Improving access is just one potential way to reduce health disparities related to influenza and influenza vaccination. Over 10 influenza seasons, higher rates of influenza-associated hospitalizations and intensive care unit admissions were observed in Black, Hispanic, and American Indian/Alaska Native people. These disparities were highest in children aged younger than 4 years and influenza-associated in-hospital deaths were three- to fourfold higher in Black, Hispanic, and Asian/Pacific Islander children, compared with White children. The reason for the disparities isn’t completely clear but increasing immunization rates may be part of the solution. During the 2020-2021 influenza season, flu immunization rates in Black children (51.6%) were lower than those seen in White (57.4%) and Hispanic children (58.9%).

The AAP’s Recommendations for Prevention and Control of Influenza in Children, 2022–2023, highlight a variety of evidence-based strategies to increase influenza immunization rates. These may provide a little inspiration for clinicians looking to try a new approach. If you wish to share your experience with increasing influenza immunization rates in your practice setting, please email me at Kristina.bryant@louisville.edu.

Dr. Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She is a member of the AAP’s Committee on Infectious Diseases and one of the lead authors of the AAP’s Recommendations for Prevention and Control of Influenza in Children, 2022–2023. The opinions expressed in this article are her own. Dr. Bryant discloses that she has served as an investigator on clinical trials funded by Pfizer, Enanta, and Gilead.

Cold and flu season came early in 2022.

On Nov. 4, 2022, the Centers for Disease Control and Prevention issued a Health Alert Network Health Advisory about early, elevated respiratory disease incidence caused by multiple viruses other than SARS-CoV-2.

Interseasonal spread of respiratory syncytial virus has continued in 2022, with RSV-associated hospitalizations increasing in the late spring and continuing throughout the summer and into the fall. In October, some regions of the country were seeing RSV activity near the peak seasonal levels typically observed in December and January.

Cases of severe respiratory infection in children who tested positive for rhinovirus or enterovirus spiked in August; further testing confirmed the presence of EV-D68 in some children. Rhinovirus and enterovirus continue to circulate and are isolated in hospitalized children with respiratory illness.

In some parts of the country, influenza cases have rapidly increased ahead of what we normally anticipate. According to preliminary estimates from the CDC, between Oct. 1 and Oct. 22, 880,000 people were sickened with flu, 420,000 people visited a health care provider for flu illness, and 6,900 people were hospitalized for flu. The cumulative hospitalization rate is higher than observed at this time of year in every previous flu season since 2010-2011. Hospitalization rates are highest in children aged 0-4 years and adults 65 years and older.

Of course, this report came as no surprise to pediatric health care providers. Many children’s hospitals had been operating at or over capacity for weeks. While a systematic assessment of the surge on children’s hospitals has not been published, anecdotally, hospitals from around the country have described record emergency department visits and inpatient census numbers. Some have set up tents or other temporary facilities to see ambulatory patients and have canceled elective surgeries because of a lack of beds.

There is no quick or easy solution to stem the tide of RSV-related or enterovirus/rhinovirus admissions, but many flu-related hospitalizations are vaccine preventable. Unfortunately, too few children are receiving influenza vaccine. As of the week ending Oct. 15, only about 22.1% of eligible children had been immunized. The American Academy of Pediatrics and the CDC recommend that all children are vaccinated, preferably by the end of October so they have time to develop immunity before influenza starts circulating. As it stands now, the majority of the nation’s children are facing a flu season without the benefits of vaccine.

There is still time to take steps to prevent this flu season from becoming one of the worst in recent memory. A strong provider recommendation for influenza vaccine is consistently associated with higher rates of vaccine acceptance. We need to recommend influenza vaccine to all eligible patients at every visit and in every setting. It will help if we can say it like we mean it. Some of us are tired of debating the merits of COVID-19 vaccine with families and may be leery of additional debates about flu. Some of us may just be tired, as many practices have already expanded office hours to care for the influx of kids with respiratory illness. On the heels of two atypical flu seasons, a few of us may be quietly complacent about the importance of flu vaccines for children.

Anyone in need of a little motivation should check out a paper recently published in Clinical Infectious Diseases that reinforces the value of flu vaccine, even in a year when there is a poor match between the vaccine and circulating viruses.

The 2019-2020 flu season was a bad flu season for children. Two antigenically drifted influenza viruses predominated and cases of influenza soared, resulting in the largest influenza epidemic in children in the United States since 1992. Pediatric Intensive Care Influenza Study investigators used a test-negative design to estimate the effectiveness of influenza vaccine in preventing critical and life-threatening influenza in children during that season. The good news: vaccination reduced the risk of critical influenza by 78% against H1N1pdm09 viruses that were well-matched to vaccine and by 47% against mismatched viruses. Vaccination was estimated to be 75% protective against antigenically drifted B-Victoria viruses. Overall vaccine effectiveness against critical illness from any influenza virus was 63% (95% confidence interval, 38%-78%).

While it might be tempting to attribute suboptimal immunization rates to vaccine hesitancy, ready availability remains an issue for some families. We need to eliminate barriers to access. While the AAP continues to emphasize immunization in the medical home, especially for the youngest infants, the 2022 policy statement suggests that vaccinating children in schools, pharmacies, and other nontraditional settings could improve immunization rates. To the extent feasible, we need to work with partners to support community-based initiatives and promote these to families who struggle to make it into the office.

Improving access is just one potential way to reduce health disparities related to influenza and influenza vaccination. Over 10 influenza seasons, higher rates of influenza-associated hospitalizations and intensive care unit admissions were observed in Black, Hispanic, and American Indian/Alaska Native people. These disparities were highest in children aged younger than 4 years and influenza-associated in-hospital deaths were three- to fourfold higher in Black, Hispanic, and Asian/Pacific Islander children, compared with White children. The reason for the disparities isn’t completely clear but increasing immunization rates may be part of the solution. During the 2020-2021 influenza season, flu immunization rates in Black children (51.6%) were lower than those seen in White (57.4%) and Hispanic children (58.9%).

The AAP’s Recommendations for Prevention and Control of Influenza in Children, 2022–2023, highlight a variety of evidence-based strategies to increase influenza immunization rates. These may provide a little inspiration for clinicians looking to try a new approach. If you wish to share your experience with increasing influenza immunization rates in your practice setting, please email me at Kristina.bryant@louisville.edu.

Dr. Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She is a member of the AAP’s Committee on Infectious Diseases and one of the lead authors of the AAP’s Recommendations for Prevention and Control of Influenza in Children, 2022–2023. The opinions expressed in this article are her own. Dr. Bryant discloses that she has served as an investigator on clinical trials funded by Pfizer, Enanta, and Gilead.

You’re rounding in the nursery and informed of the following about one of your new patients: He’s a 38-week-old infant delivered to a mother diagnosed with syphilis at 12 weeks’ gestation at her initial prenatal visit. Her rapid plasma reagin (RPR) was 1:64 and the fluorescent treponemal antibody–absorption (FTA-ABS) test was positive. By report she was appropriately treated. Maternal RPRs obtained at 18 and 28 weeks’ gestation were 1:16 and 1:4, respectively. Maternal RPR at delivery and the infant’s RPR obtained shortly after birth were both 1:4. The mother wants to know if her baby is infected.

One result of syphilis during pregnancy is intrauterine infection and resultant congenital disease in the infant. Before you answer this mother, let’s discuss syphilis.

Congenital syphilis is a significant public health problem. In 2021, there were a total of 2,677 cases reported for a rate of 74.1 per 100,000 live births. Between 2020 and 2021, the number of cases of congenital syphilis increased 24.1% (2,158-2,677 cases), concurrent with a 45.8% increase (10.7-15.6 per 100,000) in the rate of primary and secondary syphilis in women aged 15-44 years. Between 2012 and 2021, the number of cases of congenital syphilis increased 701.5% (334-2,677 cases) and the increase in rates of primary and secondary syphilis in women aged 15-44 was 642.9% over the same period.

Why are the rates of congenital syphilis increasing? Most cases result from a lack of prenatal care and thus no testing for syphilis. The next most common cause is inadequate maternal treatment.

Congenital syphilis usually is acquired through transplacental transmission of spirochetes in the maternal bloodstream. Occasionally, it occurs at delivery via direct contact with maternal lesions. It is not transmitted in breast milk. Transmission of syphilis:

• Can occur any time during pregnancy.
• Is more likely to occur in women with untreated primary or secondary disease (60%-100%).
• Is approximately 40% in those with early latent syphilis and less than 8% in mothers with late latent syphilis.
• Is higher in women coinfected with HIV since they more frequently receive no prenatal care and their disease is inadequately treated.

Coinfection with syphilis may also increase the rate of mother-to-child transmission of HIV.

Untreated early syphilis during pregnancy results in spontaneous abortion, stillbirth, or perinatal death in up to 40% of cases. Infected newborns with early congenital syphilis can be asymptomatic or have evidence of hepatosplenomegaly, generalized lymphadenopathy, nasal discharge that is occasionally bloody, rash, and skeletal abnormalities (osteochondritis and periostitis). Other manifestations include edema, hemolytic anemia, jaundice, pneumonia, pseudoparalysis, and thrombocytopenia. Asymptomatic infants may have abnormal cerebrospinal fluid findings including elevated CSF white cell count, elevated protein, and a reactive venereal disease research laboratory test.

Late congenital syphilis, defined as the onset of symptoms after 2 years of age is secondary to scarring or persistent inflammation and gumma formation in a variety of tissues. It occurs in up to 40% of cases of untreated maternal disease. Most cases can be prevented by maternal treatment and treatment of the infant within the first 3 months of life. Common clinical manifestations include interstitial keratitis, sensorineural hearing loss, frontal bossing, saddle nose, Hutchinson teeth, mulberry molars, perforation of the hard palate, anterior bowing of the tibia (saber shins), and other skeletal abnormalities.

Diagnostic tests. Maternal diagnosis is dependent upon knowing the results of both a nontreponemal (RPR, VDRL) and a confirmatory treponemal test (TP-PA, TP-EIA, TP-CIA, FTA-ABS,) before or at delivery. TP-PA is the preferred test. When maternal disease is confirmed, the newborn should have the same quantitative nontreponemal test as the mother. A confirmatory treponemal test is not required

Evaluation and treatment. It’s imperative that children born to mothers with a reactive test, regardless of their treatment status, have a thorough exam performed before hospital discharge. The provider must determine what additional interventions should be performed.

The American Academy of Pediatrics and the Centers for Disease Control and Prevention (www.cdc.gov/std/treatment-guidelines/congenital-syphilis.htm) have developed standard algorithms for the diagnostic approach and treatment of infants born to mothers with reactive serologic tests for syphilis. It is available in the Red Book for AAP members (https://publications.aap.org/redbook). Recommendations based on various scenarios for neonates up to 1 month of age include proven or highly probable congenital syphilis, possible congenital syphilis, congenital syphilis less likely, and congenital syphilis unlikely. It is beyond the scope of this article to list the criteria and evaluation for each scenario. The reader is referred to the algorithm.

If syphilis is suspected in infants or children older than 1 month, the challenge is to determine if it is untreated congenital syphilis or acquired syphilis. Maternal syphilis status should be determined. Evaluation for congenital syphilis in this age group includes CSF analysis for VDRL, cell count and protein, CBC with differential and platelets, hepatic panel, abdominal ultrasound, long-bone radiographs, chest radiograph, neuroimaging, auditory brain stem response, and HIV testing.

Let’s go back to your patient. The mother was diagnosed with syphilis during pregnancy. You confirm that she was treated with benzathine penicillin G, and the course was completed at least 4 weeks before delivery. Treatment with any other drug during pregnancy is not appropriate. The RPR has declined, and the infant’s titer is equal to or less than four times the maternal titer. The exam is significant for generalized adenopathy and slightly bloody nasal discharge. This infant has two findings consistent with congenital syphilis regardless of RPR titer or treatment status. This places him in the proven or highly probable congenital syphilis group. Management includes CSF analysis (VDRL, cell count, and protein), CBC with differential and platelet count, and treatment with penicillin G for 10 days. Additional tests as clinically indicated include: long-bone radiograph, chest radiography, aspartate aminotranferase and alanine aminotransferase levels, neuroimaging, ophthalmologic exam, and auditory brain stem response. Despite maternal treatment, this newborn has congenital syphilis. The same nontreponemal test should be obtained every 2-3 months until it is nonreactive. It should be nonreactive by 6 months. If the infection persists to 6-12 months post treatment, reevaluation including CSF analysis and retreatment may be indicated.

Congenital syphilis can be prevented by maternal screening, diagnosis, and treatment. When that fails it is up to us to diagnosis and adequately treat our patients.

Dr. Word is a pediatric infectious disease specialist and director of the Houston Travel Medicine Clinic. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.

You’re rounding in the nursery and informed of the following about one of your new patients: He’s a 38-week-old infant delivered to a mother diagnosed with syphilis at 12 weeks’ gestation at her initial prenatal visit. Her rapid plasma reagin (RPR) was 1:64 and the fluorescent treponemal antibody–absorption (FTA-ABS) test was positive. By report she was appropriately treated. Maternal RPRs obtained at 18 and 28 weeks’ gestation were 1:16 and 1:4, respectively. Maternal RPR at delivery and the infant’s RPR obtained shortly after birth were both 1:4. The mother wants to know if her baby is infected.

One result of syphilis during pregnancy is intrauterine infection and resultant congenital disease in the infant. Before you answer this mother, let’s discuss syphilis.

Congenital syphilis is a significant public health problem. In 2021, there were a total of 2,677 cases reported for a rate of 74.1 per 100,000 live births. Between 2020 and 2021, the number of cases of congenital syphilis increased 24.1% (2,158-2,677 cases), concurrent with a 45.8% increase (10.7-15.6 per 100,000) in the rate of primary and secondary syphilis in women aged 15-44 years. Between 2012 and 2021, the number of cases of congenital syphilis increased 701.5% (334-2,677 cases) and the increase in rates of primary and secondary syphilis in women aged 15-44 was 642.9% over the same period.

Why are the rates of congenital syphilis increasing? Most cases result from a lack of prenatal care and thus no testing for syphilis. The next most common cause is inadequate maternal treatment.

Congenital syphilis usually is acquired through transplacental transmission of spirochetes in the maternal bloodstream. Occasionally, it occurs at delivery via direct contact with maternal lesions. It is not transmitted in breast milk. Transmission of syphilis:

• Can occur any time during pregnancy.
• Is more likely to occur in women with untreated primary or secondary disease (60%-100%).
• Is approximately 40% in those with early latent syphilis and less than 8% in mothers with late latent syphilis.
• Is higher in women coinfected with HIV since they more frequently receive no prenatal care and their disease is inadequately treated.

Coinfection with syphilis may also increase the rate of mother-to-child transmission of HIV.

Untreated early syphilis during pregnancy results in spontaneous abortion, stillbirth, or perinatal death in up to 40% of cases. Infected newborns with early congenital syphilis can be asymptomatic or have evidence of hepatosplenomegaly, generalized lymphadenopathy, nasal discharge that is occasionally bloody, rash, and skeletal abnormalities (osteochondritis and periostitis). Other manifestations include edema, hemolytic anemia, jaundice, pneumonia, pseudoparalysis, and thrombocytopenia. Asymptomatic infants may have abnormal cerebrospinal fluid findings including elevated CSF white cell count, elevated protein, and a reactive venereal disease research laboratory test.

Late congenital syphilis, defined as the onset of symptoms after 2 years of age is secondary to scarring or persistent inflammation and gumma formation in a variety of tissues. It occurs in up to 40% of cases of untreated maternal disease. Most cases can be prevented by maternal treatment and treatment of the infant within the first 3 months of life. Common clinical manifestations include interstitial keratitis, sensorineural hearing loss, frontal bossing, saddle nose, Hutchinson teeth, mulberry molars, perforation of the hard palate, anterior bowing of the tibia (saber shins), and other skeletal abnormalities.

Diagnostic tests. Maternal diagnosis is dependent upon knowing the results of both a nontreponemal (RPR, VDRL) and a confirmatory treponemal test (TP-PA, TP-EIA, TP-CIA, FTA-ABS,) before or at delivery. TP-PA is the preferred test. When maternal disease is confirmed, the newborn should have the same quantitative nontreponemal test as the mother. A confirmatory treponemal test is not required

Evaluation and treatment. It’s imperative that children born to mothers with a reactive test, regardless of their treatment status, have a thorough exam performed before hospital discharge. The provider must determine what additional interventions should be performed.

The American Academy of Pediatrics and the Centers for Disease Control and Prevention (www.cdc.gov/std/treatment-guidelines/congenital-syphilis.htm) have developed standard algorithms for the diagnostic approach and treatment of infants born to mothers with reactive serologic tests for syphilis. It is available in the Red Book for AAP members (https://publications.aap.org/redbook). Recommendations based on various scenarios for neonates up to 1 month of age include proven or highly probable congenital syphilis, possible congenital syphilis, congenital syphilis less likely, and congenital syphilis unlikely. It is beyond the scope of this article to list the criteria and evaluation for each scenario. The reader is referred to the algorithm.

If syphilis is suspected in infants or children older than 1 month, the challenge is to determine if it is untreated congenital syphilis or acquired syphilis. Maternal syphilis status should be determined. Evaluation for congenital syphilis in this age group includes CSF analysis for VDRL, cell count and protein, CBC with differential and platelets, hepatic panel, abdominal ultrasound, long-bone radiographs, chest radiograph, neuroimaging, auditory brain stem response, and HIV testing.

Let’s go back to your patient. The mother was diagnosed with syphilis during pregnancy. You confirm that she was treated with benzathine penicillin G, and the course was completed at least 4 weeks before delivery. Treatment with any other drug during pregnancy is not appropriate. The RPR has declined, and the infant’s titer is equal to or less than four times the maternal titer. The exam is significant for generalized adenopathy and slightly bloody nasal discharge. This infant has two findings consistent with congenital syphilis regardless of RPR titer or treatment status. This places him in the proven or highly probable congenital syphilis group. Management includes CSF analysis (VDRL, cell count, and protein), CBC with differential and platelet count, and treatment with penicillin G for 10 days. Additional tests as clinically indicated include: long-bone radiograph, chest radiography, aspartate aminotranferase and alanine aminotransferase levels, neuroimaging, ophthalmologic exam, and auditory brain stem response. Despite maternal treatment, this newborn has congenital syphilis. The same nontreponemal test should be obtained every 2-3 months until it is nonreactive. It should be nonreactive by 6 months. If the infection persists to 6-12 months post treatment, reevaluation including CSF analysis and retreatment may be indicated.

Congenital syphilis can be prevented by maternal screening, diagnosis, and treatment. When that fails it is up to us to diagnosis and adequately treat our patients.

Dr. Word is a pediatric infectious disease specialist and director of the Houston Travel Medicine Clinic. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.

You’re rounding in the nursery and informed of the following about one of your new patients: He’s a 38-week-old infant delivered to a mother diagnosed with syphilis at 12 weeks’ gestation at her initial prenatal visit. Her rapid plasma reagin (RPR) was 1:64 and the fluorescent treponemal antibody–absorption (FTA-ABS) test was positive. By report she was appropriately treated. Maternal RPRs obtained at 18 and 28 weeks’ gestation were 1:16 and 1:4, respectively. Maternal RPR at delivery and the infant’s RPR obtained shortly after birth were both 1:4. The mother wants to know if her baby is infected.

One result of syphilis during pregnancy is intrauterine infection and resultant congenital disease in the infant. Before you answer this mother, let’s discuss syphilis.

Congenital syphilis is a significant public health problem. In 2021, there were a total of 2,677 cases reported for a rate of 74.1 per 100,000 live births. Between 2020 and 2021, the number of cases of congenital syphilis increased 24.1% (2,158-2,677 cases), concurrent with a 45.8% increase (10.7-15.6 per 100,000) in the rate of primary and secondary syphilis in women aged 15-44 years. Between 2012 and 2021, the number of cases of congenital syphilis increased 701.5% (334-2,677 cases) and the increase in rates of primary and secondary syphilis in women aged 15-44 was 642.9% over the same period.

Why are the rates of congenital syphilis increasing? Most cases result from a lack of prenatal care and thus no testing for syphilis. The next most common cause is inadequate maternal treatment.

Congenital syphilis usually is acquired through transplacental transmission of spirochetes in the maternal bloodstream. Occasionally, it occurs at delivery via direct contact with maternal lesions. It is not transmitted in breast milk. Transmission of syphilis:

• Can occur any time during pregnancy.
• Is more likely to occur in women with untreated primary or secondary disease (60%-100%).
• Is approximately 40% in those with early latent syphilis and less than 8% in mothers with late latent syphilis.
• Is higher in women coinfected with HIV since they more frequently receive no prenatal care and their disease is inadequately treated.

Coinfection with syphilis may also increase the rate of mother-to-child transmission of HIV.

Untreated early syphilis during pregnancy results in spontaneous abortion, stillbirth, or perinatal death in up to 40% of cases. Infected newborns with early congenital syphilis can be asymptomatic or have evidence of hepatosplenomegaly, generalized lymphadenopathy, nasal discharge that is occasionally bloody, rash, and skeletal abnormalities (osteochondritis and periostitis). Other manifestations include edema, hemolytic anemia, jaundice, pneumonia, pseudoparalysis, and thrombocytopenia. Asymptomatic infants may have abnormal cerebrospinal fluid findings including elevated CSF white cell count, elevated protein, and a reactive venereal disease research laboratory test.

Late congenital syphilis, defined as the onset of symptoms after 2 years of age is secondary to scarring or persistent inflammation and gumma formation in a variety of tissues. It occurs in up to 40% of cases of untreated maternal disease. Most cases can be prevented by maternal treatment and treatment of the infant within the first 3 months of life. Common clinical manifestations include interstitial keratitis, sensorineural hearing loss, frontal bossing, saddle nose, Hutchinson teeth, mulberry molars, perforation of the hard palate, anterior bowing of the tibia (saber shins), and other skeletal abnormalities.

Diagnostic tests. Maternal diagnosis is dependent upon knowing the results of both a nontreponemal (RPR, VDRL) and a confirmatory treponemal test (TP-PA, TP-EIA, TP-CIA, FTA-ABS,) before or at delivery. TP-PA is the preferred test. When maternal disease is confirmed, the newborn should have the same quantitative nontreponemal test as the mother. A confirmatory treponemal test is not required

Evaluation and treatment. It’s imperative that children born to mothers with a reactive test, regardless of their treatment status, have a thorough exam performed before hospital discharge. The provider must determine what additional interventions should be performed.

The American Academy of Pediatrics and the Centers for Disease Control and Prevention (www.cdc.gov/std/treatment-guidelines/congenital-syphilis.htm) have developed standard algorithms for the diagnostic approach and treatment of infants born to mothers with reactive serologic tests for syphilis. It is available in the Red Book for AAP members (https://publications.aap.org/redbook). Recommendations based on various scenarios for neonates up to 1 month of age include proven or highly probable congenital syphilis, possible congenital syphilis, congenital syphilis less likely, and congenital syphilis unlikely. It is beyond the scope of this article to list the criteria and evaluation for each scenario. The reader is referred to the algorithm.

If syphilis is suspected in infants or children older than 1 month, the challenge is to determine if it is untreated congenital syphilis or acquired syphilis. Maternal syphilis status should be determined. Evaluation for congenital syphilis in this age group includes CSF analysis for VDRL, cell count and protein, CBC with differential and platelets, hepatic panel, abdominal ultrasound, long-bone radiographs, chest radiograph, neuroimaging, auditory brain stem response, and HIV testing.

Let’s go back to your patient. The mother was diagnosed with syphilis during pregnancy. You confirm that she was treated with benzathine penicillin G, and the course was completed at least 4 weeks before delivery. Treatment with any other drug during pregnancy is not appropriate. The RPR has declined, and the infant’s titer is equal to or less than four times the maternal titer. The exam is significant for generalized adenopathy and slightly bloody nasal discharge. This infant has two findings consistent with congenital syphilis regardless of RPR titer or treatment status. This places him in the proven or highly probable congenital syphilis group. Management includes CSF analysis (VDRL, cell count, and protein), CBC with differential and platelet count, and treatment with penicillin G for 10 days. Additional tests as clinically indicated include: long-bone radiograph, chest radiography, aspartate aminotranferase and alanine aminotransferase levels, neuroimaging, ophthalmologic exam, and auditory brain stem response. Despite maternal treatment, this newborn has congenital syphilis. The same nontreponemal test should be obtained every 2-3 months until it is nonreactive. It should be nonreactive by 6 months. If the infection persists to 6-12 months post treatment, reevaluation including CSF analysis and retreatment may be indicated.

Congenital syphilis can be prevented by maternal screening, diagnosis, and treatment. When that fails it is up to us to diagnosis and adequately treat our patients.

Dr. Word is a pediatric infectious disease specialist and director of the Houston Travel Medicine Clinic. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.

Who would have thought we would need to refresh our knowledge on polio virus in 2022? Fate seems cruel to add this concern on the heels of SARS-CoV-2, monkeypox, abnormal seasons for RSV, acute flaccid myelitis (AFM) linked to enteroviruses, and a summer of parechovirus causing infant meningitis. But confirmation that indeed an adult had polio with paralytic disease raises concerns among public health groups and ordinary citizens alike, particularly those who remember polio in its heyday.

History: In the summer of 1952, polio was among the most feared diseases on the planet. Families were advised to not allow children to congregate in groups or use public swimming pools; little league baseball games were being canceled and there was talk of not opening schools for the fall. Every parent’s nightmare seemed to be the nonspecific febrile summer illness that led to paralytic sequelae. TV news included videos of the iron lung wards in hospitals across the country. Medical providers felt powerless, only able to give nonspecific preventive advice. There was no specific antiviral (there still isn’t) and vaccines seemed a long way off.

Then came the news that Dr. Jonas Salk’s group had gotten an inactivated polio vaccine (IPV) approved for general use in 1955. Families were excited to have their children vaccinated. Paralytic polio cases dropped like a rock from approximately 22,000/year in 1952 to approximately 2,200 in 1956. A surge to near 6,000 cases in 1959 led to Dr. Albert Sabin’s oral polio vaccine (OPV), which supplanted IPV in 1961. OPV had the advantages of: 1) Inducing mucosal as well as serum antibodies, 2) more durable responses, and 3) immunity in unvaccinated persons exposed to vaccine virus that had been shed in stools into wastewater and rivers.

By 1964, polio had nearly disappeared. The last wild-type indigenous U.S. case was in 1979. By 1994, all the Americas were declared polio free. Because the only U.S. paralytic polio cases thereafter were foreign imports or were associated with oral vaccine strains (so-called vaccine-associated paralytic polio [VAPP]), OPV was replaced by an enhanced IPV in 2000 to prevent further VAPP.

Polio facts: Polio is asymptomatic in about 70% of infections. Among the 30% with symptoms, paralysis occurs infrequently, with the overall rate of paralytic infections being 0.5% (rate varies by virus type with type 3 having the highest rate).¹ Why then was the world so afraid of polio? If every person in a U.S. birth cohort (about 3.7 million) was unvaccinated and became infected with poliovirus, more than 18,000 would get paralytic polio and almost 1,300 would die. Of note, adults have a higher chance of paralytic polio after infection than children.

Concerns in 2022: Persons vaccinated with at least three doses of either IPV or OPV have historically been protected from paralytic polio (99% protection). But are we sure that the United States remains protected against polio after 2 decades of IPV being the only vaccine? Polio could be reintroduced at any time to the United States from countries with reported cases that likely arose because of low vaccination rates related to war, famine, or political upheavals (Malawi, Mozambique, Nigeria, Pakistan, and Afghanistan).² The proof? The recent confirmed New York case.

International efforts resulted in global eradication of two polio wild-types viruses (type 2 in 2015 and type 3 in 2019). Nevertheless, vaccine-derived, virulent polio virus (VDPV) type 2 and VDPV-3 still circulate in some areas, particularly Africa (VDPV-2) and Israel (VDPV-3). The above-mentioned U.S. case is an unvaccinated adult traveler who went to an area where VDPV-2 circulates and developed disease after returning home.³ So, it was not an indigenous reappearance in the United States and it was not a breakthrough case in a vaccinated person. But it is sobering to realize that all who are unvaccinated remain at risk for paralytic polio in 2022, particularly because vaccination rates declined nearly everywhere during the initial COVID-19 pandemic. We are still catching up, with vaccination rates under 50% in some ZIP codes.⁴

Are VDPVs circulating in some parts of the United States? Interestingly, wastewater surveillance programs may be the most economical and practical way to perform polio surveillance. Such a program detected polio virus in London wastewater in June 2022.⁵ New York has recently detected polio in wastewater during testing begun because of the recent case.⁶

Good news: For paralytic polio, seropositivity at any titer indicates protection, so U.S. serosurveillance data would also be informative. How durable is polio protection in the IPV era? Available data suggest that even though we have used only IPV these past 20 years, seropositivity rates among vaccinees with at least three doses of either IPV or OPV should persist for decades and likely for life. Even before polio became a concern this year, the Centers for Disease Control and Prevention, being proactive, wanted to ensure that the enhanced IPV was producing durable immunity and that persons of all ages remained seropositive to the three polio virus types over 10 years after discontinuing OPV use in 2012.

The CDC collaborated with investigators in Kansas City, Mo., to evaluate titers and seropositivity to all three types in a 2- to 85-year-old otherwise healthy cohort with demographics that mirrored the 2010 census for the Kansas City region, which in turn mirrored the national 2021 census data.⁷ There were approximately 100 persons in each age cohort, with 200 below age 11 years (the cohort that had received only IPV). Serology was performed at the CDC.

Overall seropositivity rates were high, but lower for type 3 (83.3%) and type 2 (90.7%) than type 1 (94.4%). Of note, most of those seronegative for one or more types were among 2- to 3-year-olds who had not completed their full IPV series, with most seronegative results being against polio types 1 and 3. Further, five, who were confirmed as having received no polio vaccine, were seronegative for all three types. Two with no available vaccine records (over 18 years old) were also seronegative for all three types.

So, regardless of the era in which one got polio vaccine, vaccine protection appears to persist indefinitely after three doses. Even 80-year-olds were still seropositive if they had three doses. We can confidently reassure our patients that the vaccine still works; the persons who need to fear polio in 2022 are those who are not vaccinated or have had fewer than three doses, particularly if they travel to areas of persistent polio. Wild type 1 virus persists in a few countries as does VDPV type 2 and VDPV type 3. Importantly, wild type 2 and wild type 3 (with the lowest seropositivity in 2012 study) have been eliminated globally so the only circulating type 2 and type 3 polio virus is VDPV in a few countries. Travel to these countries warrants review of polio vaccine records and CDC or WHO current recommendations for travelers to those countries.
 

Dr. Harrison is a professor, University of Missouri Kansas City School of Medicine, department of medicine, infectious diseases section, Kansas City. Email him at pdnews@mdedge.com.

References

1. Poliomyelitis. World Health Organization fact sheet, 2022 Jul 4..

2. Franco-Paredes C et al. Lancet Infect Dis. 2022 Aug 16. doi: 10.1016/S1473-3099(22)00548-5.

3. Link-Gelles R et al. MMWR Morb Mortal Wkly Rep. 2022 Aug 19;71(33):1065-8.

4. “Polio vaccination rate for 2-year-olds is as low as 37% in parts of N.Y. county where paralysis case was found,” NBC News, Erika Edwards, 2022 Aug 16. 5. Vaccine-derived poliovirus type 2 (VDPV2) detected in environmental samples in London. Polioeradication.org. 2022 Jun 22.

6. “NYSDOH and NYCDOHMH wastewater monitoring identifies polio in New York City and urges unvaccinated New Yorkers to get vaccinated now,” nyc.gov. 2022 Aug 12.

7. Wallace GS et al. Hum Vaccin Immunother. 2017;13(4):776-83.

Who would have thought we would need to refresh our knowledge on polio virus in 2022? Fate seems cruel to add this concern on the heels of SARS-CoV-2, monkeypox, abnormal seasons for RSV, acute flaccid myelitis (AFM) linked to enteroviruses, and a summer of parechovirus causing infant meningitis. But confirmation that indeed an adult had polio with paralytic disease raises concerns among public health groups and ordinary citizens alike, particularly those who remember polio in its heyday.

History: In the summer of 1952, polio was among the most feared diseases on the planet. Families were advised to not allow children to congregate in groups or use public swimming pools; little league baseball games were being canceled and there was talk of not opening schools for the fall. Every parent’s nightmare seemed to be the nonspecific febrile summer illness that led to paralytic sequelae. TV news included videos of the iron lung wards in hospitals across the country. Medical providers felt powerless, only able to give nonspecific preventive advice. There was no specific antiviral (there still isn’t) and vaccines seemed a long way off.

Then came the news that Dr. Jonas Salk’s group had gotten an inactivated polio vaccine (IPV) approved for general use in 1955. Families were excited to have their children vaccinated. Paralytic polio cases dropped like a rock from approximately 22,000/year in 1952 to approximately 2,200 in 1956. A surge to near 6,000 cases in 1959 led to Dr. Albert Sabin’s oral polio vaccine (OPV), which supplanted IPV in 1961. OPV had the advantages of: 1) Inducing mucosal as well as serum antibodies, 2) more durable responses, and 3) immunity in unvaccinated persons exposed to vaccine virus that had been shed in stools into wastewater and rivers.

By 1964, polio had nearly disappeared. The last wild-type indigenous U.S. case was in 1979. By 1994, all the Americas were declared polio free. Because the only U.S. paralytic polio cases thereafter were foreign imports or were associated with oral vaccine strains (so-called vaccine-associated paralytic polio [VAPP]), OPV was replaced by an enhanced IPV in 2000 to prevent further VAPP.

Polio facts: Polio is asymptomatic in about 70% of infections. Among the 30% with symptoms, paralysis occurs infrequently, with the overall rate of paralytic infections being 0.5% (rate varies by virus type with type 3 having the highest rate).¹ Why then was the world so afraid of polio? If every person in a U.S. birth cohort (about 3.7 million) was unvaccinated and became infected with poliovirus, more than 18,000 would get paralytic polio and almost 1,300 would die. Of note, adults have a higher chance of paralytic polio after infection than children.

Concerns in 2022: Persons vaccinated with at least three doses of either IPV or OPV have historically been protected from paralytic polio (99% protection). But are we sure that the United States remains protected against polio after 2 decades of IPV being the only vaccine? Polio could be reintroduced at any time to the United States from countries with reported cases that likely arose because of low vaccination rates related to war, famine, or political upheavals (Malawi, Mozambique, Nigeria, Pakistan, and Afghanistan).² The proof? The recent confirmed New York case.

International efforts resulted in global eradication of two polio wild-types viruses (type 2 in 2015 and type 3 in 2019). Nevertheless, vaccine-derived, virulent polio virus (VDPV) type 2 and VDPV-3 still circulate in some areas, particularly Africa (VDPV-2) and Israel (VDPV-3). The above-mentioned U.S. case is an unvaccinated adult traveler who went to an area where VDPV-2 circulates and developed disease after returning home.³ So, it was not an indigenous reappearance in the United States and it was not a breakthrough case in a vaccinated person. But it is sobering to realize that all who are unvaccinated remain at risk for paralytic polio in 2022, particularly because vaccination rates declined nearly everywhere during the initial COVID-19 pandemic. We are still catching up, with vaccination rates under 50% in some ZIP codes.⁴

Are VDPVs circulating in some parts of the United States? Interestingly, wastewater surveillance programs may be the most economical and practical way to perform polio surveillance. Such a program detected polio virus in London wastewater in June 2022.⁵ New York has recently detected polio in wastewater during testing begun because of the recent case.⁶

Good news: For paralytic polio, seropositivity at any titer indicates protection, so U.S. serosurveillance data would also be informative. How durable is polio protection in the IPV era? Available data suggest that even though we have used only IPV these past 20 years, seropositivity rates among vaccinees with at least three doses of either IPV or OPV should persist for decades and likely for life. Even before polio became a concern this year, the Centers for Disease Control and Prevention, being proactive, wanted to ensure that the enhanced IPV was producing durable immunity and that persons of all ages remained seropositive to the three polio virus types over 10 years after discontinuing OPV use in 2012.

The CDC collaborated with investigators in Kansas City, Mo., to evaluate titers and seropositivity to all three types in a 2- to 85-year-old otherwise healthy cohort with demographics that mirrored the 2010 census for the Kansas City region, which in turn mirrored the national 2021 census data.⁷ There were approximately 100 persons in each age cohort, with 200 below age 11 years (the cohort that had received only IPV). Serology was performed at the CDC.

Overall seropositivity rates were high, but lower for type 3 (83.3%) and type 2 (90.7%) than type 1 (94.4%). Of note, most of those seronegative for one or more types were among 2- to 3-year-olds who had not completed their full IPV series, with most seronegative results being against polio types 1 and 3. Further, five, who were confirmed as having received no polio vaccine, were seronegative for all three types. Two with no available vaccine records (over 18 years old) were also seronegative for all three types.

So, regardless of the era in which one got polio vaccine, vaccine protection appears to persist indefinitely after three doses. Even 80-year-olds were still seropositive if they had three doses. We can confidently reassure our patients that the vaccine still works; the persons who need to fear polio in 2022 are those who are not vaccinated or have had fewer than three doses, particularly if they travel to areas of persistent polio. Wild type 1 virus persists in a few countries as does VDPV type 2 and VDPV type 3. Importantly, wild type 2 and wild type 3 (with the lowest seropositivity in 2012 study) have been eliminated globally so the only circulating type 2 and type 3 polio virus is VDPV in a few countries. Travel to these countries warrants review of polio vaccine records and CDC or WHO current recommendations for travelers to those countries.
 

Dr. Harrison is a professor, University of Missouri Kansas City School of Medicine, department of medicine, infectious diseases section, Kansas City. Email him at pdnews@mdedge.com.

References

1. Poliomyelitis. World Health Organization fact sheet, 2022 Jul 4..

2. Franco-Paredes C et al. Lancet Infect Dis. 2022 Aug 16. doi: 10.1016/S1473-3099(22)00548-5.

3. Link-Gelles R et al. MMWR Morb Mortal Wkly Rep. 2022 Aug 19;71(33):1065-8.

4. “Polio vaccination rate for 2-year-olds is as low as 37% in parts of N.Y. county where paralysis case was found,” NBC News, Erika Edwards, 2022 Aug 16. 5. Vaccine-derived poliovirus type 2 (VDPV2) detected in environmental samples in London. Polioeradication.org. 2022 Jun 22.

6. “NYSDOH and NYCDOHMH wastewater monitoring identifies polio in New York City and urges unvaccinated New Yorkers to get vaccinated now,” nyc.gov. 2022 Aug 12.

7. Wallace GS et al. Hum Vaccin Immunother. 2017;13(4):776-83.

Who would have thought we would need to refresh our knowledge on polio virus in 2022? Fate seems cruel to add this concern on the heels of SARS-CoV-2, monkeypox, abnormal seasons for RSV, acute flaccid myelitis (AFM) linked to enteroviruses, and a summer of parechovirus causing infant meningitis. But confirmation that indeed an adult had polio with paralytic disease raises concerns among public health groups and ordinary citizens alike, particularly those who remember polio in its heyday.

History: In the summer of 1952, polio was among the most feared diseases on the planet. Families were advised to not allow children to congregate in groups or use public swimming pools; little league baseball games were being canceled and there was talk of not opening schools for the fall. Every parent’s nightmare seemed to be the nonspecific febrile summer illness that led to paralytic sequelae. TV news included videos of the iron lung wards in hospitals across the country. Medical providers felt powerless, only able to give nonspecific preventive advice. There was no specific antiviral (there still isn’t) and vaccines seemed a long way off.

Then came the news that Dr. Jonas Salk’s group had gotten an inactivated polio vaccine (IPV) approved for general use in 1955. Families were excited to have their children vaccinated. Paralytic polio cases dropped like a rock from approximately 22,000/year in 1952 to approximately 2,200 in 1956. A surge to near 6,000 cases in 1959 led to Dr. Albert Sabin’s oral polio vaccine (OPV), which supplanted IPV in 1961. OPV had the advantages of: 1) Inducing mucosal as well as serum antibodies, 2) more durable responses, and 3) immunity in unvaccinated persons exposed to vaccine virus that had been shed in stools into wastewater and rivers.

By 1964, polio had nearly disappeared. The last wild-type indigenous U.S. case was in 1979. By 1994, all the Americas were declared polio free. Because the only U.S. paralytic polio cases thereafter were foreign imports or were associated with oral vaccine strains (so-called vaccine-associated paralytic polio [VAPP]), OPV was replaced by an enhanced IPV in 2000 to prevent further VAPP.

Polio facts: Polio is asymptomatic in about 70% of infections. Among the 30% with symptoms, paralysis occurs infrequently, with the overall rate of paralytic infections being 0.5% (rate varies by virus type with type 3 having the highest rate).¹ Why then was the world so afraid of polio? If every person in a U.S. birth cohort (about 3.7 million) was unvaccinated and became infected with poliovirus, more than 18,000 would get paralytic polio and almost 1,300 would die. Of note, adults have a higher chance of paralytic polio after infection than children.

Concerns in 2022: Persons vaccinated with at least three doses of either IPV or OPV have historically been protected from paralytic polio (99% protection). But are we sure that the United States remains protected against polio after 2 decades of IPV being the only vaccine? Polio could be reintroduced at any time to the United States from countries with reported cases that likely arose because of low vaccination rates related to war, famine, or political upheavals (Malawi, Mozambique, Nigeria, Pakistan, and Afghanistan).² The proof? The recent confirmed New York case.

International efforts resulted in global eradication of two polio wild-types viruses (type 2 in 2015 and type 3 in 2019). Nevertheless, vaccine-derived, virulent polio virus (VDPV) type 2 and VDPV-3 still circulate in some areas, particularly Africa (VDPV-2) and Israel (VDPV-3). The above-mentioned U.S. case is an unvaccinated adult traveler who went to an area where VDPV-2 circulates and developed disease after returning home.³ So, it was not an indigenous reappearance in the United States and it was not a breakthrough case in a vaccinated person. But it is sobering to realize that all who are unvaccinated remain at risk for paralytic polio in 2022, particularly because vaccination rates declined nearly everywhere during the initial COVID-19 pandemic. We are still catching up, with vaccination rates under 50% in some ZIP codes.⁴

Are VDPVs circulating in some parts of the United States? Interestingly, wastewater surveillance programs may be the most economical and practical way to perform polio surveillance. Such a program detected polio virus in London wastewater in June 2022.⁵ New York has recently detected polio in wastewater during testing begun because of the recent case.⁶

Good news: For paralytic polio, seropositivity at any titer indicates protection, so U.S. serosurveillance data would also be informative. How durable is polio protection in the IPV era? Available data suggest that even though we have used only IPV these past 20 years, seropositivity rates among vaccinees with at least three doses of either IPV or OPV should persist for decades and likely for life. Even before polio became a concern this year, the Centers for Disease Control and Prevention, being proactive, wanted to ensure that the enhanced IPV was producing durable immunity and that persons of all ages remained seropositive to the three polio virus types over 10 years after discontinuing OPV use in 2012.

The CDC collaborated with investigators in Kansas City, Mo., to evaluate titers and seropositivity to all three types in a 2- to 85-year-old otherwise healthy cohort with demographics that mirrored the 2010 census for the Kansas City region, which in turn mirrored the national 2021 census data.⁷ There were approximately 100 persons in each age cohort, with 200 below age 11 years (the cohort that had received only IPV). Serology was performed at the CDC.

Overall seropositivity rates were high, but lower for type 3 (83.3%) and type 2 (90.7%) than type 1 (94.4%). Of note, most of those seronegative for one or more types were among 2- to 3-year-olds who had not completed their full IPV series, with most seronegative results being against polio types 1 and 3. Further, five, who were confirmed as having received no polio vaccine, were seronegative for all three types. Two with no available vaccine records (over 18 years old) were also seronegative for all three types.

So, regardless of the era in which one got polio vaccine, vaccine protection appears to persist indefinitely after three doses. Even 80-year-olds were still seropositive if they had three doses. We can confidently reassure our patients that the vaccine still works; the persons who need to fear polio in 2022 are those who are not vaccinated or have had fewer than three doses, particularly if they travel to areas of persistent polio. Wild type 1 virus persists in a few countries as does VDPV type 2 and VDPV type 3. Importantly, wild type 2 and wild type 3 (with the lowest seropositivity in 2012 study) have been eliminated globally so the only circulating type 2 and type 3 polio virus is VDPV in a few countries. Travel to these countries warrants review of polio vaccine records and CDC or WHO current recommendations for travelers to those countries.
 

Dr. Harrison is a professor, University of Missouri Kansas City School of Medicine, department of medicine, infectious diseases section, Kansas City. Email him at pdnews@mdedge.com.

References

1. Poliomyelitis. World Health Organization fact sheet, 2022 Jul 4..

2. Franco-Paredes C et al. Lancet Infect Dis. 2022 Aug 16. doi: 10.1016/S1473-3099(22)00548-5.

3. Link-Gelles R et al. MMWR Morb Mortal Wkly Rep. 2022 Aug 19;71(33):1065-8.

4. “Polio vaccination rate for 2-year-olds is as low as 37% in parts of N.Y. county where paralysis case was found,” NBC News, Erika Edwards, 2022 Aug 16. 5. Vaccine-derived poliovirus type 2 (VDPV2) detected in environmental samples in London. Polioeradication.org. 2022 Jun 22.

6. “NYSDOH and NYCDOHMH wastewater monitoring identifies polio in New York City and urges unvaccinated New Yorkers to get vaccinated now,” nyc.gov. 2022 Aug 12.

7. Wallace GS et al. Hum Vaccin Immunother. 2017;13(4):776-83.

My group in Rochester, N.Y., examined the current pneumococcal serotypes causing AOM in children. From our data, we can determine the PCV13 vaccine types that escape prevention and cause AOM and understand what effect to expect from the new pneumococcal conjugate vaccines (PCVs) that will be coming soon. There are limited data from middle ear fluid (MEF) cultures on which to base such analyses. Tympanocentesis is the preferred method for securing MEF for culture and our group is unique in providing such data to the Centers for Disease Control and publishing our results on a periodic basis to inform clinicians.

Pneumococci are the second most common cause of acute otitis media (AOM) since the introduction of pneumococcal conjugate vaccines (PCVs) more than 2 decades ago.^1,2 Pneumococcal AOM causes more severe acute disease and more often causes suppurative complications than Haemophilus influenzae, which is the most common cause of AOM. Prevention of pneumococcal AOM will be a highly relevant contributor to cost-effectiveness analyses for the anticipated introduction of PCV15 (Merck) and PCV20 (Pfizer). Both PCV15 and PCV20 have been licensed for adult use; PCV15 licensure for infants and children occurred in June 2022 for invasive pneumococcal disease and is anticipated in the near future for PCV20. They are improvements over PCV13 because they add serotypes that cause invasive pneumococcal diseases, although less so for prevention of AOM, on the basis of our data.

Nasopharyngeal colonization is a necessary pathogenic step in progression to pneumococcal disease. However, not all strains of pneumococci expressing different capsular serotypes are equally virulent and likely to cause disease. In PCV-vaccinated populations, vaccine pressure and antibiotic resistance drive PCV serotype replacement with nonvaccine serotypes (NVTs), gradually reducing the net effectiveness of the vaccines. Therefore, knowledge of prevalent NVTs colonizing the nasopharynx identifies future pneumococcal serotypes most likely to emerge as pathogenic.

We published an effectiveness study of PCV13.³ A relative reduction of 86% in AOM caused by strains expressing PCV13 serotypes was observed in the first few years after PCV13 introduction. The greatest reduction in MEF samples was in serotype 19A, with a relative reduction of 91%. However, over time the vaccine type efficacy of PCV13 against MEF-positive pneumococcal AOM has eroded. There was no clear efficacy against serotype 3, and we still observed cases of serotype 19A and 19F. PCV13 vaccine failures have been even more frequent in Europe (nearly 30% of pneumococcal AOM in Europe is caused by vaccine serotypes) than our data indicate, where about 10% of AOM is caused by PCV13 serotypes.

In our most recent publication covering 2015-2019, we described results from 589 children, aged 6-36 months, from whom we collected 2,042 nasopharyngeal samples.^2,4 During AOM, 495 MEF samples from 319 AOM-infected children were collected (during bilateral infections, tympanocentesis was performed in both ears). Whether bacteria were isolated was based per AOM case, not per tap. The average age of children with AOM was 15 months (range 6-31 months). The three most prevalent nasopharyngeal pneumococcal serotypes were 35B, 23B, and 15B/C. Serotype 35B was the most common at AOM visits in both the nasopharynx and MEF samples followed by serotype 15B/C. Nonsusceptibility among pneumococci to penicillin, azithromycin, and multiple other antibiotics was high. Increasing resistance to ceftriaxone was also observed.

Based on our results, if PCV15 (PCV13 + 22F and 33F) effectiveness is identical to PCV13 for the included serotypes and 100% efficacy for the added serotypes is presumed, PCV15 will reduce pneumococcal AOMs by 8%, pneumococcal nasopharyngeal colonization events at onset of AOM by 6%, and pneumococcal nasopharyngeal colonization events during health by 3%. As for the projected reductions brought about by PCV20 (PCV15 + 8, 10A, 11A, 12F, and 15B), presuming serotype 15B is efficacious against serotype 15C and 100% efficacy for the added serotypes, PCV20 will reduce pneumococcal AOMs by 22%, pneumococcal nasopharyngeal colonization events at onset of AOM by 20%, and pneumococcal nasopharyngeal colonization events during health by 3% (Figure).

The CDC estimated that, in 2004, pneumococcal disease in the United States caused 4 million illness episodes, 22,000 deaths, 445,000 hospitalizations, 774,000 emergency department visits, 5 million outpatient visits, and 4.1 million outpatient antibiotic prescriptions. Direct medical costs totaled $3.5 billion. Pneumonia (866,000 cases) accounted for 22% of all cases and 72% of pneumococcal costs. AOM and sinusitis (1.5 million cases each) composed 75% of cases and 16% of direct medical costs.⁵ However, if indirect costs are taken into account, such as work loss by parents of young children, the cost of pneumococcal disease caused by AOM alone may exceed $6 billion annually⁶ and become dominant in the cost-effectiveness analysis in high-income countries.

Despite widespread use of PCV13, Pneumococcus has shown its resilience under vaccine pressure such that the organism remains a very common AOM pathogen. All-cause AOM has declined modestly and pneumococcal AOM caused by the specific serotypes in PCVs has declined dramatically since the introduction of PCVs. However, the burden of pneumococcal AOM disease is still considerable.

The notion that strains expressing serotypes that were not included in PCV7 were less virulent was proven wrong within a few years after introduction of PCV7, with the emergence of strains expressing serotype 19A, and others. The same cycle occurred after introduction of PCV13. It appears to take about 4 years after introduction of a PCV before peak effectiveness is achieved – which then begins to erode with emergence of NVTs. First, the NVTs are observed to colonize the nasopharynx as commensals and then from among those strains new disease-causing strains emerge.

At the most recent meeting of the International Society of Pneumococci and Pneumococcal Diseases in Toronto in June, many presentations focused on the fact that PCVs elicit highly effective protective serotype-specific antibodies to the capsular polysaccharides of included types. However, 100 serotypes are known. The limitations of PCVs are becoming increasingly apparent. They are costly and consume a large portion of the Vaccines for Children budget. Children in the developing world remain largely unvaccinated because of the high cost. NVTs that have emerged to cause disease vary by country, vary by adult vs. pediatric populations, and are dynamically changing year to year. Forthcoming PCVs of 15 and 20 serotypes will be even more costly than PCV13, will not include many newly emerged serotypes, and will probably likewise encounter “serotype replacement” because of high immune evasion by pneumococci.

When Merck and Pfizer made their decisions on serotype composition for PCV15 and PCV20, respectively, they were based on available data at the time regarding predominant serotypes causing invasive pneumococcal disease in countries that had the best data and would be the market for their products. However, from the time of the decision to licensure of vaccine is many years, and during that time the pneumococcal serotypes have changed, more so for AOM, and I predict more change will occur in the future.

In the past 3 years, Dr. Pichichero has received honoraria from Merck to attend 1-day consulting meetings and his institution has received investigator-initiated research grants to study aspects of PCV15. In the past 3 years, he was reimbursed for expenses to attend the ISPPD meeting in Toronto to present a poster on potential efficacy of PCV20 to prevent complicated AOM.

Dr. Pichichero is a specialist in pediatric infectious diseases, Center for Infectious Diseases and Immunology, and director of the Research Institute, at Rochester (N.Y.) General Hospital.

References

1. Kaur R et al. Pediatrics. 2017;140(3).

2. Kaur R et al. Eur J Clin Microbiol Infect Dis. 2021;41:37-44..

3. Pichichero M et al. Lancet Child Adolesc Health. 2018;2(8):561-8.

4. Zhou F et al. Pediatrics. 2008;121(2):253-60.

5. Huang SS et al. Vaccine. 2011;29(18):3398-412.

6. Casey JR and Pichichero ME. Clin Pediatr (Phila). 2014;53(9):865-73. .
 

My group in Rochester, N.Y., examined the current pneumococcal serotypes causing AOM in children. From our data, we can determine the PCV13 vaccine types that escape prevention and cause AOM and understand what effect to expect from the new pneumococcal conjugate vaccines (PCVs) that will be coming soon. There are limited data from middle ear fluid (MEF) cultures on which to base such analyses. Tympanocentesis is the preferred method for securing MEF for culture and our group is unique in providing such data to the Centers for Disease Control and publishing our results on a periodic basis to inform clinicians.

Pneumococci are the second most common cause of acute otitis media (AOM) since the introduction of pneumococcal conjugate vaccines (PCVs) more than 2 decades ago.^1,2 Pneumococcal AOM causes more severe acute disease and more often causes suppurative complications than Haemophilus influenzae, which is the most common cause of AOM. Prevention of pneumococcal AOM will be a highly relevant contributor to cost-effectiveness analyses for the anticipated introduction of PCV15 (Merck) and PCV20 (Pfizer). Both PCV15 and PCV20 have been licensed for adult use; PCV15 licensure for infants and children occurred in June 2022 for invasive pneumococcal disease and is anticipated in the near future for PCV20. They are improvements over PCV13 because they add serotypes that cause invasive pneumococcal diseases, although less so for prevention of AOM, on the basis of our data.

Nasopharyngeal colonization is a necessary pathogenic step in progression to pneumococcal disease. However, not all strains of pneumococci expressing different capsular serotypes are equally virulent and likely to cause disease. In PCV-vaccinated populations, vaccine pressure and antibiotic resistance drive PCV serotype replacement with nonvaccine serotypes (NVTs), gradually reducing the net effectiveness of the vaccines. Therefore, knowledge of prevalent NVTs colonizing the nasopharynx identifies future pneumococcal serotypes most likely to emerge as pathogenic.

We published an effectiveness study of PCV13.³ A relative reduction of 86% in AOM caused by strains expressing PCV13 serotypes was observed in the first few years after PCV13 introduction. The greatest reduction in MEF samples was in serotype 19A, with a relative reduction of 91%. However, over time the vaccine type efficacy of PCV13 against MEF-positive pneumococcal AOM has eroded. There was no clear efficacy against serotype 3, and we still observed cases of serotype 19A and 19F. PCV13 vaccine failures have been even more frequent in Europe (nearly 30% of pneumococcal AOM in Europe is caused by vaccine serotypes) than our data indicate, where about 10% of AOM is caused by PCV13 serotypes.

In our most recent publication covering 2015-2019, we described results from 589 children, aged 6-36 months, from whom we collected 2,042 nasopharyngeal samples.^2,4 During AOM, 495 MEF samples from 319 AOM-infected children were collected (during bilateral infections, tympanocentesis was performed in both ears). Whether bacteria were isolated was based per AOM case, not per tap. The average age of children with AOM was 15 months (range 6-31 months). The three most prevalent nasopharyngeal pneumococcal serotypes were 35B, 23B, and 15B/C. Serotype 35B was the most common at AOM visits in both the nasopharynx and MEF samples followed by serotype 15B/C. Nonsusceptibility among pneumococci to penicillin, azithromycin, and multiple other antibiotics was high. Increasing resistance to ceftriaxone was also observed.

Based on our results, if PCV15 (PCV13 + 22F and 33F) effectiveness is identical to PCV13 for the included serotypes and 100% efficacy for the added serotypes is presumed, PCV15 will reduce pneumococcal AOMs by 8%, pneumococcal nasopharyngeal colonization events at onset of AOM by 6%, and pneumococcal nasopharyngeal colonization events during health by 3%. As for the projected reductions brought about by PCV20 (PCV15 + 8, 10A, 11A, 12F, and 15B), presuming serotype 15B is efficacious against serotype 15C and 100% efficacy for the added serotypes, PCV20 will reduce pneumococcal AOMs by 22%, pneumococcal nasopharyngeal colonization events at onset of AOM by 20%, and pneumococcal nasopharyngeal colonization events during health by 3% (Figure).

The CDC estimated that, in 2004, pneumococcal disease in the United States caused 4 million illness episodes, 22,000 deaths, 445,000 hospitalizations, 774,000 emergency department visits, 5 million outpatient visits, and 4.1 million outpatient antibiotic prescriptions. Direct medical costs totaled $3.5 billion. Pneumonia (866,000 cases) accounted for 22% of all cases and 72% of pneumococcal costs. AOM and sinusitis (1.5 million cases each) composed 75% of cases and 16% of direct medical costs.⁵ However, if indirect costs are taken into account, such as work loss by parents of young children, the cost of pneumococcal disease caused by AOM alone may exceed $6 billion annually⁶ and become dominant in the cost-effectiveness analysis in high-income countries.

Despite widespread use of PCV13, Pneumococcus has shown its resilience under vaccine pressure such that the organism remains a very common AOM pathogen. All-cause AOM has declined modestly and pneumococcal AOM caused by the specific serotypes in PCVs has declined dramatically since the introduction of PCVs. However, the burden of pneumococcal AOM disease is still considerable.

The notion that strains expressing serotypes that were not included in PCV7 were less virulent was proven wrong within a few years after introduction of PCV7, with the emergence of strains expressing serotype 19A, and others. The same cycle occurred after introduction of PCV13. It appears to take about 4 years after introduction of a PCV before peak effectiveness is achieved – which then begins to erode with emergence of NVTs. First, the NVTs are observed to colonize the nasopharynx as commensals and then from among those strains new disease-causing strains emerge.

At the most recent meeting of the International Society of Pneumococci and Pneumococcal Diseases in Toronto in June, many presentations focused on the fact that PCVs elicit highly effective protective serotype-specific antibodies to the capsular polysaccharides of included types. However, 100 serotypes are known. The limitations of PCVs are becoming increasingly apparent. They are costly and consume a large portion of the Vaccines for Children budget. Children in the developing world remain largely unvaccinated because of the high cost. NVTs that have emerged to cause disease vary by country, vary by adult vs. pediatric populations, and are dynamically changing year to year. Forthcoming PCVs of 15 and 20 serotypes will be even more costly than PCV13, will not include many newly emerged serotypes, and will probably likewise encounter “serotype replacement” because of high immune evasion by pneumococci.

When Merck and Pfizer made their decisions on serotype composition for PCV15 and PCV20, respectively, they were based on available data at the time regarding predominant serotypes causing invasive pneumococcal disease in countries that had the best data and would be the market for their products. However, from the time of the decision to licensure of vaccine is many years, and during that time the pneumococcal serotypes have changed, more so for AOM, and I predict more change will occur in the future.

In the past 3 years, Dr. Pichichero has received honoraria from Merck to attend 1-day consulting meetings and his institution has received investigator-initiated research grants to study aspects of PCV15. In the past 3 years, he was reimbursed for expenses to attend the ISPPD meeting in Toronto to present a poster on potential efficacy of PCV20 to prevent complicated AOM.

Dr. Pichichero is a specialist in pediatric infectious diseases, Center for Infectious Diseases and Immunology, and director of the Research Institute, at Rochester (N.Y.) General Hospital.

References

1. Kaur R et al. Pediatrics. 2017;140(3).

2. Kaur R et al. Eur J Clin Microbiol Infect Dis. 2021;41:37-44..

3. Pichichero M et al. Lancet Child Adolesc Health. 2018;2(8):561-8.

4. Zhou F et al. Pediatrics. 2008;121(2):253-60.

5. Huang SS et al. Vaccine. 2011;29(18):3398-412.

6. Casey JR and Pichichero ME. Clin Pediatr (Phila). 2014;53(9):865-73. .
 

My group in Rochester, N.Y., examined the current pneumococcal serotypes causing AOM in children. From our data, we can determine the PCV13 vaccine types that escape prevention and cause AOM and understand what effect to expect from the new pneumococcal conjugate vaccines (PCVs) that will be coming soon. There are limited data from middle ear fluid (MEF) cultures on which to base such analyses. Tympanocentesis is the preferred method for securing MEF for culture and our group is unique in providing such data to the Centers for Disease Control and publishing our results on a periodic basis to inform clinicians.

Pneumococci are the second most common cause of acute otitis media (AOM) since the introduction of pneumococcal conjugate vaccines (PCVs) more than 2 decades ago.^1,2 Pneumococcal AOM causes more severe acute disease and more often causes suppurative complications than Haemophilus influenzae, which is the most common cause of AOM. Prevention of pneumococcal AOM will be a highly relevant contributor to cost-effectiveness analyses for the anticipated introduction of PCV15 (Merck) and PCV20 (Pfizer). Both PCV15 and PCV20 have been licensed for adult use; PCV15 licensure for infants and children occurred in June 2022 for invasive pneumococcal disease and is anticipated in the near future for PCV20. They are improvements over PCV13 because they add serotypes that cause invasive pneumococcal diseases, although less so for prevention of AOM, on the basis of our data.

Nasopharyngeal colonization is a necessary pathogenic step in progression to pneumococcal disease. However, not all strains of pneumococci expressing different capsular serotypes are equally virulent and likely to cause disease. In PCV-vaccinated populations, vaccine pressure and antibiotic resistance drive PCV serotype replacement with nonvaccine serotypes (NVTs), gradually reducing the net effectiveness of the vaccines. Therefore, knowledge of prevalent NVTs colonizing the nasopharynx identifies future pneumococcal serotypes most likely to emerge as pathogenic.

We published an effectiveness study of PCV13.³ A relative reduction of 86% in AOM caused by strains expressing PCV13 serotypes was observed in the first few years after PCV13 introduction. The greatest reduction in MEF samples was in serotype 19A, with a relative reduction of 91%. However, over time the vaccine type efficacy of PCV13 against MEF-positive pneumococcal AOM has eroded. There was no clear efficacy against serotype 3, and we still observed cases of serotype 19A and 19F. PCV13 vaccine failures have been even more frequent in Europe (nearly 30% of pneumococcal AOM in Europe is caused by vaccine serotypes) than our data indicate, where about 10% of AOM is caused by PCV13 serotypes.

In our most recent publication covering 2015-2019, we described results from 589 children, aged 6-36 months, from whom we collected 2,042 nasopharyngeal samples.^2,4 During AOM, 495 MEF samples from 319 AOM-infected children were collected (during bilateral infections, tympanocentesis was performed in both ears). Whether bacteria were isolated was based per AOM case, not per tap. The average age of children with AOM was 15 months (range 6-31 months). The three most prevalent nasopharyngeal pneumococcal serotypes were 35B, 23B, and 15B/C. Serotype 35B was the most common at AOM visits in both the nasopharynx and MEF samples followed by serotype 15B/C. Nonsusceptibility among pneumococci to penicillin, azithromycin, and multiple other antibiotics was high. Increasing resistance to ceftriaxone was also observed.

Based on our results, if PCV15 (PCV13 + 22F and 33F) effectiveness is identical to PCV13 for the included serotypes and 100% efficacy for the added serotypes is presumed, PCV15 will reduce pneumococcal AOMs by 8%, pneumococcal nasopharyngeal colonization events at onset of AOM by 6%, and pneumococcal nasopharyngeal colonization events during health by 3%. As for the projected reductions brought about by PCV20 (PCV15 + 8, 10A, 11A, 12F, and 15B), presuming serotype 15B is efficacious against serotype 15C and 100% efficacy for the added serotypes, PCV20 will reduce pneumococcal AOMs by 22%, pneumococcal nasopharyngeal colonization events at onset of AOM by 20%, and pneumococcal nasopharyngeal colonization events during health by 3% (Figure).

The CDC estimated that, in 2004, pneumococcal disease in the United States caused 4 million illness episodes, 22,000 deaths, 445,000 hospitalizations, 774,000 emergency department visits, 5 million outpatient visits, and 4.1 million outpatient antibiotic prescriptions. Direct medical costs totaled $3.5 billion. Pneumonia (866,000 cases) accounted for 22% of all cases and 72% of pneumococcal costs. AOM and sinusitis (1.5 million cases each) composed 75% of cases and 16% of direct medical costs.⁵ However, if indirect costs are taken into account, such as work loss by parents of young children, the cost of pneumococcal disease caused by AOM alone may exceed $6 billion annually⁶ and become dominant in the cost-effectiveness analysis in high-income countries.

Despite widespread use of PCV13, Pneumococcus has shown its resilience under vaccine pressure such that the organism remains a very common AOM pathogen. All-cause AOM has declined modestly and pneumococcal AOM caused by the specific serotypes in PCVs has declined dramatically since the introduction of PCVs. However, the burden of pneumococcal AOM disease is still considerable.

The notion that strains expressing serotypes that were not included in PCV7 were less virulent was proven wrong within a few years after introduction of PCV7, with the emergence of strains expressing serotype 19A, and others. The same cycle occurred after introduction of PCV13. It appears to take about 4 years after introduction of a PCV before peak effectiveness is achieved – which then begins to erode with emergence of NVTs. First, the NVTs are observed to colonize the nasopharynx as commensals and then from among those strains new disease-causing strains emerge.

At the most recent meeting of the International Society of Pneumococci and Pneumococcal Diseases in Toronto in June, many presentations focused on the fact that PCVs elicit highly effective protective serotype-specific antibodies to the capsular polysaccharides of included types. However, 100 serotypes are known. The limitations of PCVs are becoming increasingly apparent. They are costly and consume a large portion of the Vaccines for Children budget. Children in the developing world remain largely unvaccinated because of the high cost. NVTs that have emerged to cause disease vary by country, vary by adult vs. pediatric populations, and are dynamically changing year to year. Forthcoming PCVs of 15 and 20 serotypes will be even more costly than PCV13, will not include many newly emerged serotypes, and will probably likewise encounter “serotype replacement” because of high immune evasion by pneumococci.

When Merck and Pfizer made their decisions on serotype composition for PCV15 and PCV20, respectively, they were based on available data at the time regarding predominant serotypes causing invasive pneumococcal disease in countries that had the best data and would be the market for their products. However, from the time of the decision to licensure of vaccine is many years, and during that time the pneumococcal serotypes have changed, more so for AOM, and I predict more change will occur in the future.

In the past 3 years, Dr. Pichichero has received honoraria from Merck to attend 1-day consulting meetings and his institution has received investigator-initiated research grants to study aspects of PCV15. In the past 3 years, he was reimbursed for expenses to attend the ISPPD meeting in Toronto to present a poster on potential efficacy of PCV20 to prevent complicated AOM.

Dr. Pichichero is a specialist in pediatric infectious diseases, Center for Infectious Diseases and Immunology, and director of the Research Institute, at Rochester (N.Y.) General Hospital.

References

1. Kaur R et al. Pediatrics. 2017;140(3).

2. Kaur R et al. Eur J Clin Microbiol Infect Dis. 2021;41:37-44..

3. Pichichero M et al. Lancet Child Adolesc Health. 2018;2(8):561-8.

4. Zhou F et al. Pediatrics. 2008;121(2):253-60.

5. Huang SS et al. Vaccine. 2011;29(18):3398-412.

6. Casey JR and Pichichero ME. Clin Pediatr (Phila). 2014;53(9):865-73. .
 

A family’s decision to vaccinate their child is best made jointly with a trusted medical provider who knows the child and family. The American Academy of Pediatrics created a toolkit with resources for answering questions about the recently authorized SARS-CoV-2 mRNA vaccines (Pfizer and Moderna) for 6-month- to 5-year-olds with science-backed vaccine facts, including links to other useful AAP information websites, talking points, graphics, and videos.¹

SARS-CoV-2 seasonality

SARS-CoV-2 is now endemic, not a once-a-year seasonal virus. Seasons (aka surges) will occur whenever a new variant arises (twice yearly since 2020, Omicron BA.4/BA.5 currently), or when enough vaccine holdouts, newborns, and/or those with waning of prior immunity (vaccine or infection induced) accrue.

Emergency use authorization submission data for mRNA vaccine responses in young children^2,3

Moderna in 6-month- through 5-year-olds. Two 25-mcg doses given 4-8 weeks apart produced 37.8% (95% confidence interval, 20.9%-51.1%) protection against symptomatic Omicron SARS-CoV-2 infections through 3 months of follow-up. Immunobridging analysis of antibody responses compared to 18- to 25-year-olds (100-mcg doses) showed the children’s responses were noninferior. Thus, the committee inferred that vaccine effectiveness in children should be similar to that in 18- to 25-year-olds. Fever, irritability, or local reaction/pain occurred in two-thirds after the second dose. Grade 3 reactions were noted in less than 5%.

Pfizer in 6-month- through 4-year-olds. Three 3-mcg doses, two doses 3-8 weeks apart and the third dose at least 8 weeks later (median 16 weeks), produced 80.3% (95% CI, 13.9%-96.7%) protection against symptomatic COVID-19 during the 6 weeks after the third dose. Local and systemic reactions occurred in 63.8%; less than 5% had grade 3 reactions (fever in about 3%, irritability in 1.3%, fatigue in 0.8%) mostly after second dose.

Neither duration of follow-up is very long. The Moderna data tell me that a third primary dose would have been better but restarting the trial to evaluate third doses would have delayed Moderna’s EUA another 4-6 months. The three-dose Pfizer data look better but may not have been as good with another 6 weeks of follow-up.

Additional post-EUA data will be collected. Boosters will be needed when immunity from both vaccines wanes (one estimate is about 6 months after the primary series). The Advisory Committee on Immunization Practices noted in their deliberations that vaccine-induced antibody responses are higher and cross-neutralize variants (even Omicron) better than infection-induced immunity.⁴

Are there downsides to the vaccines? Naysayers question vaccinating children less than 5 years old with reasons containing enough “truth” that they catch people’s attention, for example, “young children don’t get very sick with COVID-19,” “most have been infected already,” “RNA for the spike protein stays in the body for months,” or “myocarditis.” Naysayers can quote references in reputable journals but seem to spin selected data out of context or quote unconfirmed data from the Vaccine Adverse Event Reporting System.
 

Reasons to vaccinate

• While children have milder disease than adults, mid-June 2022 surveillance indicated 50 hospitalizations and 1 pediatric death each day from SARS-CoV-2.⁵
• Vaccinating young children endows a foundation of vaccine-induced SARS-CoV-2 immunity that is superior to infection-induced immunity.⁴
• Long-term effects of large numbers of SARS-CoV-2 particles that enter every organ of a developing child have not been determined.
• Viral loads are lowered by prior vaccine; fewer viral replications lessen chances for newer variants to arise.
• Transmission is less in breakthrough infections than infections in the unvaccinated.
• Thirty percent of 5- to 11-year-olds hospitalized for SARS-CoV-2 had no underlying conditions;⁶ hospitalization rates in newborn to 4-year-olds have been the highest in the Omicron surge.⁷
• No myocarditis or pericarditis episodes have been detected in 6-month- to 11-year-old trials.
• The AAP and ACIP recommend the mRNA vaccines.

My thoughts are that SARS-CoV-2 vaccine is just another “routine” childhood vaccine that prepares children for healthier futures, pandemic or not, and the vaccines are as safe as other routine vaccines.

And like other pediatric vaccines, it should be no surprise that boosters will be needed, even if no newer variants than Omicron BA.4/BA.5 arise. But we know newer variants will arise and, similar to influenza vaccine, new formulations, perhaps with multiple SARS-CoV-2 strain antigens, will be needed every year or so. Everyone will get SARS-CoV-2 multiple times in their lives no matter how careful they are. So isn’t it good medical practice to establish early the best available foundation for maintaining lifelong SARS-CoV-2 immunity?

To me it is like pertussis. Most pertussis-infected children are sick enough to be hospitalized; very few die. They are miserable with illnesses that take weeks to months to subside. The worst disease usually occurs in unvaccinated young children or those with underlying conditions. Reactogenicity was reduced with acellular vaccine but resulted in less immunogenicity, so we give boosters at intervals that best match waning immunity. Circulating strains can be different than the vaccine strain, so protection against infection is 80%. Finally, even the safest vaccine may very rarely have sequelae. That is why The National Vaccine Injury Compensation Program was created. Yet the benefit-to-harm ratio for children and society favors universal pertussis vaccine use. And we vaccinate even those who have had pertussis because even infection-based immunity is incomplete and protection wanes. If arguments similar to those by SARS-CoV-2 vaccine naysayers were applied to acellular pertussis vaccine, it seems they would argue against pertussis vaccine for young children.

Another major issue has been “safety concerns” about the vaccines’ small amount of mRNA for the spike protein encased in microscopic lipid bubbles injected in the arm or leg. This mRNA is picked up by human cells, and in the cytoplasm (not the nucleus where our DNA resides) produces a limited supply of spike protein that is then picked up by antigen-presenting cells for short-lived distribution (days to 2 weeks at most) to regional lymph nodes where immune-memory processes are jump-started. Contrast that to even asymptomatic SARS-CoV-2 infection where multibillions of virus particles are produced for up to 14 days with access to every bodily organ that contains ACE-2 receptors (they all do). Each virus particle hijacks a human cell producing thousands of mRNA for spike protein (and multiple other SARS-CoV-2 proteins), eventually releasing multibillions of lipid fragments from the ruptured cell. Comparing the amount of these components in the mRNA vaccines to those from infection is like comparing a campfire to the many-thousand-acre wildfire. So, if one is worried about the effects of spike protein and lipid fragments, the limited localized amounts in mRNA vaccines should make one much less concerned than the enormous amounts circulating throughout the body as a result of a SARS-CoV-2 infection.

My take is that children 6-months to 5-years-old deserve SARS-CoV-2–induced vaccine protection and we can and should strongly recommend it as medical providers and child advocates.
 

*Dr. Harrison is professor, University of Missouri Kansas City School of Medicine, department of medicine, infectious diseases section, Kansas City. Email him at pdnews@mdedge.com.

References

1. AAP. 2022 Jun 21. As COVID-19 vaccines become available for children ages 6 months to 4 years, AAP urges families to reach out to pediatricians to ask questions and access vaccine. www.aap.org.

2. CDC. Grading of recommendations, assessment, development, and evaluation (GRADE): Moderna COVID-19 vaccine for children aged 6 months–5 years. www.cdc.gov.

3. CDC. ACIP evidence to recommendations for use of Moderna COVID-19 vaccine in children ages 6 months–5 years and Pfizer-BioNTech COVID-19 vaccine in children ages 6 months–4 years under an emergency use authorization. www.cdc.gov.

4. Tang J et al. Nat Commun. 2022;13:2979.

5. Children and COVID-19: State Data Report. 2022 Jun 30. www.aap.org.

6. Shi DS et al. MMWR Morb Mortal Wkly Rep. 2022;71:574-81.

7. Marks KJ et al. MMWR Morb Mortal Wkly Rep. 2022;71:429-36.
 

Other good resources for families are https://getvaccineanswers.org/ or www.mayoclinic.org/diseases-conditions/coronavirus/in-depth/coronavirus-in-babies-and-children/art-20484405.

*This story was updated on July 19, 2022.

A family’s decision to vaccinate their child is best made jointly with a trusted medical provider who knows the child and family. The American Academy of Pediatrics created a toolkit with resources for answering questions about the recently authorized SARS-CoV-2 mRNA vaccines (Pfizer and Moderna) for 6-month- to 5-year-olds with science-backed vaccine facts, including links to other useful AAP information websites, talking points, graphics, and videos.¹

SARS-CoV-2 seasonality

SARS-CoV-2 is now endemic, not a once-a-year seasonal virus. Seasons (aka surges) will occur whenever a new variant arises (twice yearly since 2020, Omicron BA.4/BA.5 currently), or when enough vaccine holdouts, newborns, and/or those with waning of prior immunity (vaccine or infection induced) accrue.

Emergency use authorization submission data for mRNA vaccine responses in young children^2,3

Moderna in 6-month- through 5-year-olds. Two 25-mcg doses given 4-8 weeks apart produced 37.8% (95% confidence interval, 20.9%-51.1%) protection against symptomatic Omicron SARS-CoV-2 infections through 3 months of follow-up. Immunobridging analysis of antibody responses compared to 18- to 25-year-olds (100-mcg doses) showed the children’s responses were noninferior. Thus, the committee inferred that vaccine effectiveness in children should be similar to that in 18- to 25-year-olds. Fever, irritability, or local reaction/pain occurred in two-thirds after the second dose. Grade 3 reactions were noted in less than 5%.

Pfizer in 6-month- through 4-year-olds. Three 3-mcg doses, two doses 3-8 weeks apart and the third dose at least 8 weeks later (median 16 weeks), produced 80.3% (95% CI, 13.9%-96.7%) protection against symptomatic COVID-19 during the 6 weeks after the third dose. Local and systemic reactions occurred in 63.8%; less than 5% had grade 3 reactions (fever in about 3%, irritability in 1.3%, fatigue in 0.8%) mostly after second dose.

Neither duration of follow-up is very long. The Moderna data tell me that a third primary dose would have been better but restarting the trial to evaluate third doses would have delayed Moderna’s EUA another 4-6 months. The three-dose Pfizer data look better but may not have been as good with another 6 weeks of follow-up.

Additional post-EUA data will be collected. Boosters will be needed when immunity from both vaccines wanes (one estimate is about 6 months after the primary series). The Advisory Committee on Immunization Practices noted in their deliberations that vaccine-induced antibody responses are higher and cross-neutralize variants (even Omicron) better than infection-induced immunity.⁴

Are there downsides to the vaccines? Naysayers question vaccinating children less than 5 years old with reasons containing enough “truth” that they catch people’s attention, for example, “young children don’t get very sick with COVID-19,” “most have been infected already,” “RNA for the spike protein stays in the body for months,” or “myocarditis.” Naysayers can quote references in reputable journals but seem to spin selected data out of context or quote unconfirmed data from the Vaccine Adverse Event Reporting System.
 

Reasons to vaccinate

• While children have milder disease than adults, mid-June 2022 surveillance indicated 50 hospitalizations and 1 pediatric death each day from SARS-CoV-2.⁵
• Vaccinating young children endows a foundation of vaccine-induced SARS-CoV-2 immunity that is superior to infection-induced immunity.⁴
• Long-term effects of large numbers of SARS-CoV-2 particles that enter every organ of a developing child have not been determined.
• Viral loads are lowered by prior vaccine; fewer viral replications lessen chances for newer variants to arise.
• Transmission is less in breakthrough infections than infections in the unvaccinated.
• Thirty percent of 5- to 11-year-olds hospitalized for SARS-CoV-2 had no underlying conditions;⁶ hospitalization rates in newborn to 4-year-olds have been the highest in the Omicron surge.⁷
• No myocarditis or pericarditis episodes have been detected in 6-month- to 11-year-old trials.
• The AAP and ACIP recommend the mRNA vaccines.

My thoughts are that SARS-CoV-2 vaccine is just another “routine” childhood vaccine that prepares children for healthier futures, pandemic or not, and the vaccines are as safe as other routine vaccines.

And like other pediatric vaccines, it should be no surprise that boosters will be needed, even if no newer variants than Omicron BA.4/BA.5 arise. But we know newer variants will arise and, similar to influenza vaccine, new formulations, perhaps with multiple SARS-CoV-2 strain antigens, will be needed every year or so. Everyone will get SARS-CoV-2 multiple times in their lives no matter how careful they are. So isn’t it good medical practice to establish early the best available foundation for maintaining lifelong SARS-CoV-2 immunity?

To me it is like pertussis. Most pertussis-infected children are sick enough to be hospitalized; very few die. They are miserable with illnesses that take weeks to months to subside. The worst disease usually occurs in unvaccinated young children or those with underlying conditions. Reactogenicity was reduced with acellular vaccine but resulted in less immunogenicity, so we give boosters at intervals that best match waning immunity. Circulating strains can be different than the vaccine strain, so protection against infection is 80%. Finally, even the safest vaccine may very rarely have sequelae. That is why The National Vaccine Injury Compensation Program was created. Yet the benefit-to-harm ratio for children and society favors universal pertussis vaccine use. And we vaccinate even those who have had pertussis because even infection-based immunity is incomplete and protection wanes. If arguments similar to those by SARS-CoV-2 vaccine naysayers were applied to acellular pertussis vaccine, it seems they would argue against pertussis vaccine for young children.

Another major issue has been “safety concerns” about the vaccines’ small amount of mRNA for the spike protein encased in microscopic lipid bubbles injected in the arm or leg. This mRNA is picked up by human cells, and in the cytoplasm (not the nucleus where our DNA resides) produces a limited supply of spike protein that is then picked up by antigen-presenting cells for short-lived distribution (days to 2 weeks at most) to regional lymph nodes where immune-memory processes are jump-started. Contrast that to even asymptomatic SARS-CoV-2 infection where multibillions of virus particles are produced for up to 14 days with access to every bodily organ that contains ACE-2 receptors (they all do). Each virus particle hijacks a human cell producing thousands of mRNA for spike protein (and multiple other SARS-CoV-2 proteins), eventually releasing multibillions of lipid fragments from the ruptured cell. Comparing the amount of these components in the mRNA vaccines to those from infection is like comparing a campfire to the many-thousand-acre wildfire. So, if one is worried about the effects of spike protein and lipid fragments, the limited localized amounts in mRNA vaccines should make one much less concerned than the enormous amounts circulating throughout the body as a result of a SARS-CoV-2 infection.

My take is that children 6-months to 5-years-old deserve SARS-CoV-2–induced vaccine protection and we can and should strongly recommend it as medical providers and child advocates.
 

*Dr. Harrison is professor, University of Missouri Kansas City School of Medicine, department of medicine, infectious diseases section, Kansas City. Email him at pdnews@mdedge.com.

References

1. AAP. 2022 Jun 21. As COVID-19 vaccines become available for children ages 6 months to 4 years, AAP urges families to reach out to pediatricians to ask questions and access vaccine. www.aap.org.

2. CDC. Grading of recommendations, assessment, development, and evaluation (GRADE): Moderna COVID-19 vaccine for children aged 6 months–5 years. www.cdc.gov.

3. CDC. ACIP evidence to recommendations for use of Moderna COVID-19 vaccine in children ages 6 months–5 years and Pfizer-BioNTech COVID-19 vaccine in children ages 6 months–4 years under an emergency use authorization. www.cdc.gov.

4. Tang J et al. Nat Commun. 2022;13:2979.

5. Children and COVID-19: State Data Report. 2022 Jun 30. www.aap.org.

6. Shi DS et al. MMWR Morb Mortal Wkly Rep. 2022;71:574-81.

7. Marks KJ et al. MMWR Morb Mortal Wkly Rep. 2022;71:429-36.
 

Other good resources for families are https://getvaccineanswers.org/ or www.mayoclinic.org/diseases-conditions/coronavirus/in-depth/coronavirus-in-babies-and-children/art-20484405.

*This story was updated on July 19, 2022.

A family’s decision to vaccinate their child is best made jointly with a trusted medical provider who knows the child and family. The American Academy of Pediatrics created a toolkit with resources for answering questions about the recently authorized SARS-CoV-2 mRNA vaccines (Pfizer and Moderna) for 6-month- to 5-year-olds with science-backed vaccine facts, including links to other useful AAP information websites, talking points, graphics, and videos.¹

SARS-CoV-2 seasonality

SARS-CoV-2 is now endemic, not a once-a-year seasonal virus. Seasons (aka surges) will occur whenever a new variant arises (twice yearly since 2020, Omicron BA.4/BA.5 currently), or when enough vaccine holdouts, newborns, and/or those with waning of prior immunity (vaccine or infection induced) accrue.

Emergency use authorization submission data for mRNA vaccine responses in young children^2,3

Moderna in 6-month- through 5-year-olds. Two 25-mcg doses given 4-8 weeks apart produced 37.8% (95% confidence interval, 20.9%-51.1%) protection against symptomatic Omicron SARS-CoV-2 infections through 3 months of follow-up. Immunobridging analysis of antibody responses compared to 18- to 25-year-olds (100-mcg doses) showed the children’s responses were noninferior. Thus, the committee inferred that vaccine effectiveness in children should be similar to that in 18- to 25-year-olds. Fever, irritability, or local reaction/pain occurred in two-thirds after the second dose. Grade 3 reactions were noted in less than 5%.

Pfizer in 6-month- through 4-year-olds. Three 3-mcg doses, two doses 3-8 weeks apart and the third dose at least 8 weeks later (median 16 weeks), produced 80.3% (95% CI, 13.9%-96.7%) protection against symptomatic COVID-19 during the 6 weeks after the third dose. Local and systemic reactions occurred in 63.8%; less than 5% had grade 3 reactions (fever in about 3%, irritability in 1.3%, fatigue in 0.8%) mostly after second dose.

Neither duration of follow-up is very long. The Moderna data tell me that a third primary dose would have been better but restarting the trial to evaluate third doses would have delayed Moderna’s EUA another 4-6 months. The three-dose Pfizer data look better but may not have been as good with another 6 weeks of follow-up.

Additional post-EUA data will be collected. Boosters will be needed when immunity from both vaccines wanes (one estimate is about 6 months after the primary series). The Advisory Committee on Immunization Practices noted in their deliberations that vaccine-induced antibody responses are higher and cross-neutralize variants (even Omicron) better than infection-induced immunity.⁴

Are there downsides to the vaccines? Naysayers question vaccinating children less than 5 years old with reasons containing enough “truth” that they catch people’s attention, for example, “young children don’t get very sick with COVID-19,” “most have been infected already,” “RNA for the spike protein stays in the body for months,” or “myocarditis.” Naysayers can quote references in reputable journals but seem to spin selected data out of context or quote unconfirmed data from the Vaccine Adverse Event Reporting System.
 

Reasons to vaccinate

• While children have milder disease than adults, mid-June 2022 surveillance indicated 50 hospitalizations and 1 pediatric death each day from SARS-CoV-2.⁵
• Vaccinating young children endows a foundation of vaccine-induced SARS-CoV-2 immunity that is superior to infection-induced immunity.⁴
• Long-term effects of large numbers of SARS-CoV-2 particles that enter every organ of a developing child have not been determined.
• Viral loads are lowered by prior vaccine; fewer viral replications lessen chances for newer variants to arise.
• Transmission is less in breakthrough infections than infections in the unvaccinated.
• Thirty percent of 5- to 11-year-olds hospitalized for SARS-CoV-2 had no underlying conditions;⁶ hospitalization rates in newborn to 4-year-olds have been the highest in the Omicron surge.⁷
• No myocarditis or pericarditis episodes have been detected in 6-month- to 11-year-old trials.
• The AAP and ACIP recommend the mRNA vaccines.

My thoughts are that SARS-CoV-2 vaccine is just another “routine” childhood vaccine that prepares children for healthier futures, pandemic or not, and the vaccines are as safe as other routine vaccines.

And like other pediatric vaccines, it should be no surprise that boosters will be needed, even if no newer variants than Omicron BA.4/BA.5 arise. But we know newer variants will arise and, similar to influenza vaccine, new formulations, perhaps with multiple SARS-CoV-2 strain antigens, will be needed every year or so. Everyone will get SARS-CoV-2 multiple times in their lives no matter how careful they are. So isn’t it good medical practice to establish early the best available foundation for maintaining lifelong SARS-CoV-2 immunity?

To me it is like pertussis. Most pertussis-infected children are sick enough to be hospitalized; very few die. They are miserable with illnesses that take weeks to months to subside. The worst disease usually occurs in unvaccinated young children or those with underlying conditions. Reactogenicity was reduced with acellular vaccine but resulted in less immunogenicity, so we give boosters at intervals that best match waning immunity. Circulating strains can be different than the vaccine strain, so protection against infection is 80%. Finally, even the safest vaccine may very rarely have sequelae. That is why The National Vaccine Injury Compensation Program was created. Yet the benefit-to-harm ratio for children and society favors universal pertussis vaccine use. And we vaccinate even those who have had pertussis because even infection-based immunity is incomplete and protection wanes. If arguments similar to those by SARS-CoV-2 vaccine naysayers were applied to acellular pertussis vaccine, it seems they would argue against pertussis vaccine for young children.

Another major issue has been “safety concerns” about the vaccines’ small amount of mRNA for the spike protein encased in microscopic lipid bubbles injected in the arm or leg. This mRNA is picked up by human cells, and in the cytoplasm (not the nucleus where our DNA resides) produces a limited supply of spike protein that is then picked up by antigen-presenting cells for short-lived distribution (days to 2 weeks at most) to regional lymph nodes where immune-memory processes are jump-started. Contrast that to even asymptomatic SARS-CoV-2 infection where multibillions of virus particles are produced for up to 14 days with access to every bodily organ that contains ACE-2 receptors (they all do). Each virus particle hijacks a human cell producing thousands of mRNA for spike protein (and multiple other SARS-CoV-2 proteins), eventually releasing multibillions of lipid fragments from the ruptured cell. Comparing the amount of these components in the mRNA vaccines to those from infection is like comparing a campfire to the many-thousand-acre wildfire. So, if one is worried about the effects of spike protein and lipid fragments, the limited localized amounts in mRNA vaccines should make one much less concerned than the enormous amounts circulating throughout the body as a result of a SARS-CoV-2 infection.

My take is that children 6-months to 5-years-old deserve SARS-CoV-2–induced vaccine protection and we can and should strongly recommend it as medical providers and child advocates.
 

*Dr. Harrison is professor, University of Missouri Kansas City School of Medicine, department of medicine, infectious diseases section, Kansas City. Email him at pdnews@mdedge.com.

References

1. AAP. 2022 Jun 21. As COVID-19 vaccines become available for children ages 6 months to 4 years, AAP urges families to reach out to pediatricians to ask questions and access vaccine. www.aap.org.

2. CDC. Grading of recommendations, assessment, development, and evaluation (GRADE): Moderna COVID-19 vaccine for children aged 6 months–5 years. www.cdc.gov.

3. CDC. ACIP evidence to recommendations for use of Moderna COVID-19 vaccine in children ages 6 months–5 years and Pfizer-BioNTech COVID-19 vaccine in children ages 6 months–4 years under an emergency use authorization. www.cdc.gov.

4. Tang J et al. Nat Commun. 2022;13:2979.

5. Children and COVID-19: State Data Report. 2022 Jun 30. www.aap.org.

6. Shi DS et al. MMWR Morb Mortal Wkly Rep. 2022;71:574-81.

7. Marks KJ et al. MMWR Morb Mortal Wkly Rep. 2022;71:429-36.
 

Other good resources for families are https://getvaccineanswers.org/ or www.mayoclinic.org/diseases-conditions/coronavirus/in-depth/coronavirus-in-babies-and-children/art-20484405.

*This story was updated on July 19, 2022.

Not long ago, a pediatrician working in a local urgent care clinic called me about a teenage girl with a pruritic rash. She described vesicles and pustules located primarily on the face and arms with no surrounding cellulitis or other exam findings.

“She probably has impetigo,” my colleague said. “But I took a travel and exposure history and learned that her grandma had recently returned home from visiting family in the Congo. Do you think I need to worry about monkeypox?”

While most pediatricians in the United States have never seen a case of monkeypox, the virus is not new. An orthopox, it belongs to the same genus that includes smallpox and cowpox viruses. It was discovered in 1958 when two colonies of monkeys kept for research developed pox-like rashes. The earliest human case was reported in 1970 in the Democratic Republic of Congo and now the virus is endemic in some counties in Central and West Africa.

Monkeypox virus is a zoonotic disease – it can spread from animals to people. Rodents and other small mammals – not monkeys – are thought to be the most likely reservoir. The virus typically spreads from person to person through close contact with skin or respiratory secretions or contact with contaminated fomites. Typical infection begins with fever, lymphadenopathy, and flulike symptoms that include headache and malaise. One to four days after the onset of fever, the characteristic rash begins as macular lesions that evolve into papules, then vesicles, and finally pustules. Pustular lesions are deep-seated, well circumscribed, and are usually the same size and in the same stage of development on a given body site. The rash often starts on the face or the mouth, and then moves to the extremities, including the palms and soles. Over time, the lesions umbilicate and ultimately crust over.

On May 20, the Centers for Disease Control and Prevention issued a Health Advisory describing a case of monkeypox in a patient in Massachusetts. A single case normally wouldn’t cause too much alarm. In fact, there were two cases reported in the United States in 2021, both in travelers returning to the United States from Nigeria, a country in which the virus is endemic. No transmissions from these individuals to close contacts were identified.

The Massachusetts case was remarkable for two reasons. It occurred in an individual who had recently returned from a trip to Canada, which is not a country in which the virus is endemic. Additionally, it occurred in the context of a global outbreak of monkey pox that has, to date, disproportionately affected individuals who identify as men who have sex with men. Patients have often lacked the characteristic prodrome and many have had rash localized to the perianal and genital area, with or without symptoms of proctitis (anorectal pain, tenesmus, and bleeding). Clinically, some lesions mimicked sexually transmitted infections that the occur in the anogenital area, including herpes, syphilis, and lymphogranuloma venereum.

As of May 31, 2022, 17 persons in nine states had been diagnosed with presumed monkeypox virus infection. They ranged in age from 28 to 61 years and 16/17 identified as MSM. Fourteen reported international travel in the 3 weeks before developing symptoms. As of June 12, that number had grown to 53, while worldwide the number of confirmed and suspected cases reached 1,584. Up-to-date case counts are available at https://ourworldindata.org/monkeypox.

Back on the phone, my colleague laughed a little nervously. “I guess I’m not really worried about monkeypox in my patient.” She paused and then asked, “This isn’t going to be the next pandemic, is it?”

Public health experts at the Centers for Disease Control and Prevention and the World Health Organization have been reassuring in that regard. Two vaccines are available for the prevention of monkeypox. JYNNEOS is a nonreplicating live viral vaccine licensed as a two-dose series to prevent both monkeypox and smallpox. ACAM 2000 is a live Vaccinia virus preparation licensed to prevent smallpox. These vaccines are effective when given before exposure but are thought to also beneficial when given as postexposure prophylaxis. According to the CDC, vaccination within 4 days of exposure can prevent the development of disease. Vaccination within 14 days of exposure may not prevent the development of disease but may lessen symptoms. Treatment is generally supportive but antiviral therapy could be considered for individuals with severe disease. Tecovirmat is Food and Drug Administration approved for the treatment of smallpox but is available under nonresearch Expanded Access Investigational New Drug (EA-IND) protocol for the treatment of children and adults with severe orthopox infections, including monkeypox.

So, what’s a pediatrician to do? Take a good travel history, as my colleague did, because that is good medicine. At this point in an outbreak though, a lack of travel does not exclude the diagnosis. Perform a thorough exam of skin and mucosal areas. When there are rashes in the genital or perianal area, consider the possibility of monkeypox in addition to typical sexually transmitted infections. Ask about exposure to other persons with similar rashes, as well as close or intimate contact with a persons in a social network experiencing monkeypox infections. This includes MSM who meet partners through an online website, app, or at social events. Monkeypox can also be spread through contact with an animal (dead or alive) that is an African endemic species or use of a product derived from such animals. Public health experts encourage clinicians to be alert for rash illnesses consistent with monkeypox, regardless of a patient’s gender or sexual orientation, history of international travel, or specific risk factors.

Pediatricians see many kids with rashes, and while cases of monkeypox climb daily, the disease is still very rare. Given the media coverage of the outbreak, pediatricians should be prepared for questions from patients and their parents. Clinicians who suspect a case of monkeypox should contact their local or state health department for guidance and the need for testing. Tips for recognizing monkeypox and distinguishing it from more common viral illnesses such as chicken pox are available at www.cdc.gov/poxvirus/monkeypox/clinicians/clinical-recognition.html.

Dr. Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.

Not long ago, a pediatrician working in a local urgent care clinic called me about a teenage girl with a pruritic rash. She described vesicles and pustules located primarily on the face and arms with no surrounding cellulitis or other exam findings.

“She probably has impetigo,” my colleague said. “But I took a travel and exposure history and learned that her grandma had recently returned home from visiting family in the Congo. Do you think I need to worry about monkeypox?”

While most pediatricians in the United States have never seen a case of monkeypox, the virus is not new. An orthopox, it belongs to the same genus that includes smallpox and cowpox viruses. It was discovered in 1958 when two colonies of monkeys kept for research developed pox-like rashes. The earliest human case was reported in 1970 in the Democratic Republic of Congo and now the virus is endemic in some counties in Central and West Africa.

Monkeypox virus is a zoonotic disease – it can spread from animals to people. Rodents and other small mammals – not monkeys – are thought to be the most likely reservoir. The virus typically spreads from person to person through close contact with skin or respiratory secretions or contact with contaminated fomites. Typical infection begins with fever, lymphadenopathy, and flulike symptoms that include headache and malaise. One to four days after the onset of fever, the characteristic rash begins as macular lesions that evolve into papules, then vesicles, and finally pustules. Pustular lesions are deep-seated, well circumscribed, and are usually the same size and in the same stage of development on a given body site. The rash often starts on the face or the mouth, and then moves to the extremities, including the palms and soles. Over time, the lesions umbilicate and ultimately crust over.

On May 20, the Centers for Disease Control and Prevention issued a Health Advisory describing a case of monkeypox in a patient in Massachusetts. A single case normally wouldn’t cause too much alarm. In fact, there were two cases reported in the United States in 2021, both in travelers returning to the United States from Nigeria, a country in which the virus is endemic. No transmissions from these individuals to close contacts were identified.

The Massachusetts case was remarkable for two reasons. It occurred in an individual who had recently returned from a trip to Canada, which is not a country in which the virus is endemic. Additionally, it occurred in the context of a global outbreak of monkey pox that has, to date, disproportionately affected individuals who identify as men who have sex with men. Patients have often lacked the characteristic prodrome and many have had rash localized to the perianal and genital area, with or without symptoms of proctitis (anorectal pain, tenesmus, and bleeding). Clinically, some lesions mimicked sexually transmitted infections that the occur in the anogenital area, including herpes, syphilis, and lymphogranuloma venereum.

As of May 31, 2022, 17 persons in nine states had been diagnosed with presumed monkeypox virus infection. They ranged in age from 28 to 61 years and 16/17 identified as MSM. Fourteen reported international travel in the 3 weeks before developing symptoms. As of June 12, that number had grown to 53, while worldwide the number of confirmed and suspected cases reached 1,584. Up-to-date case counts are available at https://ourworldindata.org/monkeypox.

Back on the phone, my colleague laughed a little nervously. “I guess I’m not really worried about monkeypox in my patient.” She paused and then asked, “This isn’t going to be the next pandemic, is it?”

Public health experts at the Centers for Disease Control and Prevention and the World Health Organization have been reassuring in that regard. Two vaccines are available for the prevention of monkeypox. JYNNEOS is a nonreplicating live viral vaccine licensed as a two-dose series to prevent both monkeypox and smallpox. ACAM 2000 is a live Vaccinia virus preparation licensed to prevent smallpox. These vaccines are effective when given before exposure but are thought to also beneficial when given as postexposure prophylaxis. According to the CDC, vaccination within 4 days of exposure can prevent the development of disease. Vaccination within 14 days of exposure may not prevent the development of disease but may lessen symptoms. Treatment is generally supportive but antiviral therapy could be considered for individuals with severe disease. Tecovirmat is Food and Drug Administration approved for the treatment of smallpox but is available under nonresearch Expanded Access Investigational New Drug (EA-IND) protocol for the treatment of children and adults with severe orthopox infections, including monkeypox.

So, what’s a pediatrician to do? Take a good travel history, as my colleague did, because that is good medicine. At this point in an outbreak though, a lack of travel does not exclude the diagnosis. Perform a thorough exam of skin and mucosal areas. When there are rashes in the genital or perianal area, consider the possibility of monkeypox in addition to typical sexually transmitted infections. Ask about exposure to other persons with similar rashes, as well as close or intimate contact with a persons in a social network experiencing monkeypox infections. This includes MSM who meet partners through an online website, app, or at social events. Monkeypox can also be spread through contact with an animal (dead or alive) that is an African endemic species or use of a product derived from such animals. Public health experts encourage clinicians to be alert for rash illnesses consistent with monkeypox, regardless of a patient’s gender or sexual orientation, history of international travel, or specific risk factors.

Pediatricians see many kids with rashes, and while cases of monkeypox climb daily, the disease is still very rare. Given the media coverage of the outbreak, pediatricians should be prepared for questions from patients and their parents. Clinicians who suspect a case of monkeypox should contact their local or state health department for guidance and the need for testing. Tips for recognizing monkeypox and distinguishing it from more common viral illnesses such as chicken pox are available at www.cdc.gov/poxvirus/monkeypox/clinicians/clinical-recognition.html.

Dr. Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.

Not long ago, a pediatrician working in a local urgent care clinic called me about a teenage girl with a pruritic rash. She described vesicles and pustules located primarily on the face and arms with no surrounding cellulitis or other exam findings.

“She probably has impetigo,” my colleague said. “But I took a travel and exposure history and learned that her grandma had recently returned home from visiting family in the Congo. Do you think I need to worry about monkeypox?”

While most pediatricians in the United States have never seen a case of monkeypox, the virus is not new. An orthopox, it belongs to the same genus that includes smallpox and cowpox viruses. It was discovered in 1958 when two colonies of monkeys kept for research developed pox-like rashes. The earliest human case was reported in 1970 in the Democratic Republic of Congo and now the virus is endemic in some counties in Central and West Africa.

Monkeypox virus is a zoonotic disease – it can spread from animals to people. Rodents and other small mammals – not monkeys – are thought to be the most likely reservoir. The virus typically spreads from person to person through close contact with skin or respiratory secretions or contact with contaminated fomites. Typical infection begins with fever, lymphadenopathy, and flulike symptoms that include headache and malaise. One to four days after the onset of fever, the characteristic rash begins as macular lesions that evolve into papules, then vesicles, and finally pustules. Pustular lesions are deep-seated, well circumscribed, and are usually the same size and in the same stage of development on a given body site. The rash often starts on the face or the mouth, and then moves to the extremities, including the palms and soles. Over time, the lesions umbilicate and ultimately crust over.

On May 20, the Centers for Disease Control and Prevention issued a Health Advisory describing a case of monkeypox in a patient in Massachusetts. A single case normally wouldn’t cause too much alarm. In fact, there were two cases reported in the United States in 2021, both in travelers returning to the United States from Nigeria, a country in which the virus is endemic. No transmissions from these individuals to close contacts were identified.

The Massachusetts case was remarkable for two reasons. It occurred in an individual who had recently returned from a trip to Canada, which is not a country in which the virus is endemic. Additionally, it occurred in the context of a global outbreak of monkey pox that has, to date, disproportionately affected individuals who identify as men who have sex with men. Patients have often lacked the characteristic prodrome and many have had rash localized to the perianal and genital area, with or without symptoms of proctitis (anorectal pain, tenesmus, and bleeding). Clinically, some lesions mimicked sexually transmitted infections that the occur in the anogenital area, including herpes, syphilis, and lymphogranuloma venereum.

As of May 31, 2022, 17 persons in nine states had been diagnosed with presumed monkeypox virus infection. They ranged in age from 28 to 61 years and 16/17 identified as MSM. Fourteen reported international travel in the 3 weeks before developing symptoms. As of June 12, that number had grown to 53, while worldwide the number of confirmed and suspected cases reached 1,584. Up-to-date case counts are available at https://ourworldindata.org/monkeypox.

Back on the phone, my colleague laughed a little nervously. “I guess I’m not really worried about monkeypox in my patient.” She paused and then asked, “This isn’t going to be the next pandemic, is it?”

Public health experts at the Centers for Disease Control and Prevention and the World Health Organization have been reassuring in that regard. Two vaccines are available for the prevention of monkeypox. JYNNEOS is a nonreplicating live viral vaccine licensed as a two-dose series to prevent both monkeypox and smallpox. ACAM 2000 is a live Vaccinia virus preparation licensed to prevent smallpox. These vaccines are effective when given before exposure but are thought to also beneficial when given as postexposure prophylaxis. According to the CDC, vaccination within 4 days of exposure can prevent the development of disease. Vaccination within 14 days of exposure may not prevent the development of disease but may lessen symptoms. Treatment is generally supportive but antiviral therapy could be considered for individuals with severe disease. Tecovirmat is Food and Drug Administration approved for the treatment of smallpox but is available under nonresearch Expanded Access Investigational New Drug (EA-IND) protocol for the treatment of children and adults with severe orthopox infections, including monkeypox.

So, what’s a pediatrician to do? Take a good travel history, as my colleague did, because that is good medicine. At this point in an outbreak though, a lack of travel does not exclude the diagnosis. Perform a thorough exam of skin and mucosal areas. When there are rashes in the genital or perianal area, consider the possibility of monkeypox in addition to typical sexually transmitted infections. Ask about exposure to other persons with similar rashes, as well as close or intimate contact with a persons in a social network experiencing monkeypox infections. This includes MSM who meet partners through an online website, app, or at social events. Monkeypox can also be spread through contact with an animal (dead or alive) that is an African endemic species or use of a product derived from such animals. Public health experts encourage clinicians to be alert for rash illnesses consistent with monkeypox, regardless of a patient’s gender or sexual orientation, history of international travel, or specific risk factors.

Pediatricians see many kids with rashes, and while cases of monkeypox climb daily, the disease is still very rare. Given the media coverage of the outbreak, pediatricians should be prepared for questions from patients and their parents. Clinicians who suspect a case of monkeypox should contact their local or state health department for guidance and the need for testing. Tips for recognizing monkeypox and distinguishing it from more common viral illnesses such as chicken pox are available at www.cdc.gov/poxvirus/monkeypox/clinicians/clinical-recognition.html.

Dr. Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.

The U.S. immunization program is one of the best public health success stories. Physicians who provide care for children are familiar with the routine childhood immunization schedule and administer a measles-containing vaccine at age-appropriate times. Thanks to its rigorous implementation and acceptance, endemic measles (absence of continuous virus transmission for > 1 year) was eliminated in the U.S. in 2000. Loss of this status was in jeopardy in 2019 when 22 measles outbreaks occurred in 17 states (7 were multistate outbreaks). That year, 1,163 cases were reported.¹ Most cases occurred in unvaccinated persons (89%) and 81 cases were imported of which 54 were in U.S. citizens returning from international travel. All outbreaks were linked to travel. Fortunately, the outbreaks were controlled prior to the elimination deadline, or the United States would have lost its measles elimination status. Restrictions on travel because of COVID-19 have relaxed significantly since the introduction of COVID-19 vaccines, resulting in increased regional and international travel. Multiple countries, including the United States noted a decline in routine immunizations rates during the last 2 years. Recent U.S. data for the 2020-2021 school year indicates that MMR immunizations rates (two doses) for kindergarteners declined to 93.9% (range 78.9% to > 98.9%), while the overall percentage of those students with an exemption remained low at 2.2%. Vaccine coverage greater than 95% was reported in only 16 states. Coverage of less than 90% was reported in seven states and the District of Columbia (Georgia, Idaho, Kentucky, Maryland, Minnesota, Ohio, and Wisconsin).² Vaccine coverage should be 95% or higher to maintain herd immunity and control outbreaks.

Why is measles prevention so important? Many physicians practicing in the United States today have never seen a case or know its potential complications. I saw my first case as a resident in an immigrant child. It took our training director to point out the subtle signs and symptoms. It was the first time I saw Kolpik spots. Measles is transmitted person to person via large respiratory droplets and less often by airborne spread. It is highly contagious for susceptible individuals with an attack rate of 90%. In this case, a medical student on the team developed symptoms about 10 days later. Six years would pass before I diagnosed my next case of measles. An HIV patient acquired it after close contact with someone who was in the prodromal stage. He presented with the 3 C’s: Cough, coryza, and conjunctivitis, in addition to fever and an erythematous rash. He did not recover from complications of the disease.

Prior to the routine administration of a measles vaccine, 3-4 million cases with almost 500 deaths occurred annually in the United States. Worldwide, 35 million cases and more than 6 million deaths occurred each year. Here, most patients recover completely; however, complications including otitis media, pneumonia, croup, and encephalitis can develop. Complications commonly occur in immunocompromised individuals and young children. Groups with the highest fatality rates include children aged less than 5 years, immunocompromised persons, and pregnant women. Worldwide, fatality rates are dependent on the patients underlying nutritional and health status in addition to the quality of health care available.³

Measles vaccine was licensed in 1963 and cases began to decline (Figure 1). There was a resurgence in 1989 but it was not limited to the United States. The cause of the U.S. resurgence was multifactorial: Widespread viral transmission among unvaccinated preschool-age children residing in inner cities, outbreaks in vaccinated school-age children, outbreaks in students and personnel on college campuses, and primary vaccine failure (2%-5% of recipients failed to have an adequate response). In 1989, to help prevent future outbreaks, the United States recommended a two-dose schedule for measles and in 1993, the Vaccines for Children Program, a federally funded program, was established to improve access to vaccines for all children.
 

What is going on internationally?

Figure 2 lists the top 10 countries with current measles outbreaks.

Most countries on the list may not be typical travel destinations for tourists; however, they are common destinations for individuals visiting friends and relatives after immigrating to the United States. In contrast to the United States, most countries with limited resources and infrastructure have mass-vaccination campaigns to ensure vaccine administration to large segments of the population. They too have been affected by the COVID-19 pandemic. By report, at least 41 countries delayed implementation of their measles campaign in 2020 and 2021, thus, leading to the potential for even larger outbreaks.⁴

Progress toward the global elimination of measles is evidenced by the following: All 194 countries now include one dose of measles in their routine schedules; between 2000 and 2019 coverage of one dose of measles increased from 72% to 85% and countries with more than 90% coverage increased from 45% to 63%. Finally, the number of countries offering two doses of measles increased from 50% to 91% and vaccine coverage increased from 18% to 71% over the same time period.³

What can you do for your patients and their parents before they travel abroad?

• Inform all staff that the MMR vaccine can be administered to children as young as 6 months and at times other than those listed on the routine immunization schedule. This will help avoid parents seeking vaccine being denied an appointment.
• Children 6-11 months need 1 dose of MMR. Two additional doses will still need to be administered at the routine time.
• Children 12 months or older need 2 doses of MMR at least 4 weeks apart.
• If yellow fever vaccine is needed, coordinate administration with a travel medicine clinic since both are live vaccines and must be given on the same day.
• Any person born after 1956 should have 2 doses of MMR at least 4 weeks apart if they have no evidence of immunity.
• Encourage parents to always inform you and your staff of any international travel plans.

Moving forward, remember this increased global activity and the presence of inadequately vaccinated individuals/communities keeps the United States at continued risk for measles outbreaks. The source of the next outbreak may only be one plane ride away.

Dr. Word is a pediatric infectious disease specialist and director of the Houston Travel Medicine Clinic. She said she had no relevant financial disclosures.

This article was updated 6/29/22.

References

1. Patel M et al. MMWR. 2019 Oct 11; 68(40):893-6.

2. Seither R et al. MMWR. 2022 Apr 22;71(16):561-8.

3. Gastañaduy PA et al. J Infect Dis. 2021 Sep 30;224(12 Suppl 2):S420-8. doi: 10.1093/infdis/jiaa793.

4. Centers for Disease Control and Prevention. Measles (Rubeola). http://www.CDC.gov/Measles.

The U.S. immunization program is one of the best public health success stories. Physicians who provide care for children are familiar with the routine childhood immunization schedule and administer a measles-containing vaccine at age-appropriate times. Thanks to its rigorous implementation and acceptance, endemic measles (absence of continuous virus transmission for > 1 year) was eliminated in the U.S. in 2000. Loss of this status was in jeopardy in 2019 when 22 measles outbreaks occurred in 17 states (7 were multistate outbreaks). That year, 1,163 cases were reported.¹ Most cases occurred in unvaccinated persons (89%) and 81 cases were imported of which 54 were in U.S. citizens returning from international travel. All outbreaks were linked to travel. Fortunately, the outbreaks were controlled prior to the elimination deadline, or the United States would have lost its measles elimination status. Restrictions on travel because of COVID-19 have relaxed significantly since the introduction of COVID-19 vaccines, resulting in increased regional and international travel. Multiple countries, including the United States noted a decline in routine immunizations rates during the last 2 years. Recent U.S. data for the 2020-2021 school year indicates that MMR immunizations rates (two doses) for kindergarteners declined to 93.9% (range 78.9% to > 98.9%), while the overall percentage of those students with an exemption remained low at 2.2%. Vaccine coverage greater than 95% was reported in only 16 states. Coverage of less than 90% was reported in seven states and the District of Columbia (Georgia, Idaho, Kentucky, Maryland, Minnesota, Ohio, and Wisconsin).² Vaccine coverage should be 95% or higher to maintain herd immunity and control outbreaks.

Why is measles prevention so important? Many physicians practicing in the United States today have never seen a case or know its potential complications. I saw my first case as a resident in an immigrant child. It took our training director to point out the subtle signs and symptoms. It was the first time I saw Kolpik spots. Measles is transmitted person to person via large respiratory droplets and less often by airborne spread. It is highly contagious for susceptible individuals with an attack rate of 90%. In this case, a medical student on the team developed symptoms about 10 days later. Six years would pass before I diagnosed my next case of measles. An HIV patient acquired it after close contact with someone who was in the prodromal stage. He presented with the 3 C’s: Cough, coryza, and conjunctivitis, in addition to fever and an erythematous rash. He did not recover from complications of the disease.

Prior to the routine administration of a measles vaccine, 3-4 million cases with almost 500 deaths occurred annually in the United States. Worldwide, 35 million cases and more than 6 million deaths occurred each year. Here, most patients recover completely; however, complications including otitis media, pneumonia, croup, and encephalitis can develop. Complications commonly occur in immunocompromised individuals and young children. Groups with the highest fatality rates include children aged less than 5 years, immunocompromised persons, and pregnant women. Worldwide, fatality rates are dependent on the patients underlying nutritional and health status in addition to the quality of health care available.³

Measles vaccine was licensed in 1963 and cases began to decline (Figure 1). There was a resurgence in 1989 but it was not limited to the United States. The cause of the U.S. resurgence was multifactorial: Widespread viral transmission among unvaccinated preschool-age children residing in inner cities, outbreaks in vaccinated school-age children, outbreaks in students and personnel on college campuses, and primary vaccine failure (2%-5% of recipients failed to have an adequate response). In 1989, to help prevent future outbreaks, the United States recommended a two-dose schedule for measles and in 1993, the Vaccines for Children Program, a federally funded program, was established to improve access to vaccines for all children.
 

What is going on internationally?

Figure 2 lists the top 10 countries with current measles outbreaks.

Most countries on the list may not be typical travel destinations for tourists; however, they are common destinations for individuals visiting friends and relatives after immigrating to the United States. In contrast to the United States, most countries with limited resources and infrastructure have mass-vaccination campaigns to ensure vaccine administration to large segments of the population. They too have been affected by the COVID-19 pandemic. By report, at least 41 countries delayed implementation of their measles campaign in 2020 and 2021, thus, leading to the potential for even larger outbreaks.⁴

Progress toward the global elimination of measles is evidenced by the following: All 194 countries now include one dose of measles in their routine schedules; between 2000 and 2019 coverage of one dose of measles increased from 72% to 85% and countries with more than 90% coverage increased from 45% to 63%. Finally, the number of countries offering two doses of measles increased from 50% to 91% and vaccine coverage increased from 18% to 71% over the same time period.³

What can you do for your patients and their parents before they travel abroad?

• Inform all staff that the MMR vaccine can be administered to children as young as 6 months and at times other than those listed on the routine immunization schedule. This will help avoid parents seeking vaccine being denied an appointment.
• Children 6-11 months need 1 dose of MMR. Two additional doses will still need to be administered at the routine time.
• Children 12 months or older need 2 doses of MMR at least 4 weeks apart.
• If yellow fever vaccine is needed, coordinate administration with a travel medicine clinic since both are live vaccines and must be given on the same day.
• Any person born after 1956 should have 2 doses of MMR at least 4 weeks apart if they have no evidence of immunity.
• Encourage parents to always inform you and your staff of any international travel plans.

Moving forward, remember this increased global activity and the presence of inadequately vaccinated individuals/communities keeps the United States at continued risk for measles outbreaks. The source of the next outbreak may only be one plane ride away.

Dr. Word is a pediatric infectious disease specialist and director of the Houston Travel Medicine Clinic. She said she had no relevant financial disclosures.

This article was updated 6/29/22.

References

1. Patel M et al. MMWR. 2019 Oct 11; 68(40):893-6.

2. Seither R et al. MMWR. 2022 Apr 22;71(16):561-8.

3. Gastañaduy PA et al. J Infect Dis. 2021 Sep 30;224(12 Suppl 2):S420-8. doi: 10.1093/infdis/jiaa793.

4. Centers for Disease Control and Prevention. Measles (Rubeola). http://www.CDC.gov/Measles.

The U.S. immunization program is one of the best public health success stories. Physicians who provide care for children are familiar with the routine childhood immunization schedule and administer a measles-containing vaccine at age-appropriate times. Thanks to its rigorous implementation and acceptance, endemic measles (absence of continuous virus transmission for > 1 year) was eliminated in the U.S. in 2000. Loss of this status was in jeopardy in 2019 when 22 measles outbreaks occurred in 17 states (7 were multistate outbreaks). That year, 1,163 cases were reported.¹ Most cases occurred in unvaccinated persons (89%) and 81 cases were imported of which 54 were in U.S. citizens returning from international travel. All outbreaks were linked to travel. Fortunately, the outbreaks were controlled prior to the elimination deadline, or the United States would have lost its measles elimination status. Restrictions on travel because of COVID-19 have relaxed significantly since the introduction of COVID-19 vaccines, resulting in increased regional and international travel. Multiple countries, including the United States noted a decline in routine immunizations rates during the last 2 years. Recent U.S. data for the 2020-2021 school year indicates that MMR immunizations rates (two doses) for kindergarteners declined to 93.9% (range 78.9% to > 98.9%), while the overall percentage of those students with an exemption remained low at 2.2%. Vaccine coverage greater than 95% was reported in only 16 states. Coverage of less than 90% was reported in seven states and the District of Columbia (Georgia, Idaho, Kentucky, Maryland, Minnesota, Ohio, and Wisconsin).² Vaccine coverage should be 95% or higher to maintain herd immunity and control outbreaks.

Why is measles prevention so important? Many physicians practicing in the United States today have never seen a case or know its potential complications. I saw my first case as a resident in an immigrant child. It took our training director to point out the subtle signs and symptoms. It was the first time I saw Kolpik spots. Measles is transmitted person to person via large respiratory droplets and less often by airborne spread. It is highly contagious for susceptible individuals with an attack rate of 90%. In this case, a medical student on the team developed symptoms about 10 days later. Six years would pass before I diagnosed my next case of measles. An HIV patient acquired it after close contact with someone who was in the prodromal stage. He presented with the 3 C’s: Cough, coryza, and conjunctivitis, in addition to fever and an erythematous rash. He did not recover from complications of the disease.

Prior to the routine administration of a measles vaccine, 3-4 million cases with almost 500 deaths occurred annually in the United States. Worldwide, 35 million cases and more than 6 million deaths occurred each year. Here, most patients recover completely; however, complications including otitis media, pneumonia, croup, and encephalitis can develop. Complications commonly occur in immunocompromised individuals and young children. Groups with the highest fatality rates include children aged less than 5 years, immunocompromised persons, and pregnant women. Worldwide, fatality rates are dependent on the patients underlying nutritional and health status in addition to the quality of health care available.³

Measles vaccine was licensed in 1963 and cases began to decline (Figure 1). There was a resurgence in 1989 but it was not limited to the United States. The cause of the U.S. resurgence was multifactorial: Widespread viral transmission among unvaccinated preschool-age children residing in inner cities, outbreaks in vaccinated school-age children, outbreaks in students and personnel on college campuses, and primary vaccine failure (2%-5% of recipients failed to have an adequate response). In 1989, to help prevent future outbreaks, the United States recommended a two-dose schedule for measles and in 1993, the Vaccines for Children Program, a federally funded program, was established to improve access to vaccines for all children.
 

What is going on internationally?

Figure 2 lists the top 10 countries with current measles outbreaks.

Most countries on the list may not be typical travel destinations for tourists; however, they are common destinations for individuals visiting friends and relatives after immigrating to the United States. In contrast to the United States, most countries with limited resources and infrastructure have mass-vaccination campaigns to ensure vaccine administration to large segments of the population. They too have been affected by the COVID-19 pandemic. By report, at least 41 countries delayed implementation of their measles campaign in 2020 and 2021, thus, leading to the potential for even larger outbreaks.⁴

Progress toward the global elimination of measles is evidenced by the following: All 194 countries now include one dose of measles in their routine schedules; between 2000 and 2019 coverage of one dose of measles increased from 72% to 85% and countries with more than 90% coverage increased from 45% to 63%. Finally, the number of countries offering two doses of measles increased from 50% to 91% and vaccine coverage increased from 18% to 71% over the same time period.³

What can you do for your patients and their parents before they travel abroad?

• Inform all staff that the MMR vaccine can be administered to children as young as 6 months and at times other than those listed on the routine immunization schedule. This will help avoid parents seeking vaccine being denied an appointment.
• Children 6-11 months need 1 dose of MMR. Two additional doses will still need to be administered at the routine time.
• Children 12 months or older need 2 doses of MMR at least 4 weeks apart.
• If yellow fever vaccine is needed, coordinate administration with a travel medicine clinic since both are live vaccines and must be given on the same day.
• Any person born after 1956 should have 2 doses of MMR at least 4 weeks apart if they have no evidence of immunity.
• Encourage parents to always inform you and your staff of any international travel plans.

Moving forward, remember this increased global activity and the presence of inadequately vaccinated individuals/communities keeps the United States at continued risk for measles outbreaks. The source of the next outbreak may only be one plane ride away.

Dr. Word is a pediatric infectious disease specialist and director of the Houston Travel Medicine Clinic. She said she had no relevant financial disclosures.

This article was updated 6/29/22.

References

1. Patel M et al. MMWR. 2019 Oct 11; 68(40):893-6.

2. Seither R et al. MMWR. 2022 Apr 22;71(16):561-8.

3. Gastañaduy PA et al. J Infect Dis. 2021 Sep 30;224(12 Suppl 2):S420-8. doi: 10.1093/infdis/jiaa793.

4. Centers for Disease Control and Prevention. Measles (Rubeola). http://www.CDC.gov/Measles.

In this column I have previously discussed the microbiome and its importance to health, especially as it relates to infections in children. Given the appreciated connection between microbiome and immunity, my group in Rochester, N.Y., recently undertook a study of the effect of antibiotic usage on the immune response to routine early childhood vaccines. In mouse models, it was previously shown that antibiotic exposure induced a reduction in the abundance and diversity of gut microbiota that in turn negatively affected the generation and maintenance of vaccine-induced immunity.^1,2 A study from Stanford University was the first experimental human trial of antibiotic effects on vaccine responses. Adult volunteers were given an antibiotic or not before seasonal influenza vaccination and the researchers identified specific bacteria in the gut that were reduced by the antibiotics given. Those normal bacteria in the gut microbiome were shown to provide positive immunity signals to the systemic immune system that potentiated vaccine responses.³

My group conducted the first-ever study in children to explore whether an association existed between antibiotic use and vaccine-induced antibody levels. In the May issue of Pediatrics we report results from 560 children studied.⁴ From these children, 11,888 serum antibody levels to vaccine antigens were measured. Vaccine-induced antibody levels were determined at various time points after primary vaccination at child age 2, 4, and 6 months and boosters at age 12-18 months for 10 antigens included in four vaccines: DTaP, Hib, IPV, and PCV. The antibody levels to vaccine components were measured to DTaP (diphtheria toxoid, pertussis toxoid, tetanus toxoid, pertactin, and filamentous hemagglutinin), Hib conjugate (polyribosylribitol phosphate), IPV (polio 2), and PCV (serotypes 6B, 14, and 23F). A total of 342 children with 1,678 antibiotic courses prescribed were compared with 218 children with no antibiotic exposures. The predominant antibiotics prescribed were amoxicillin, cefdinir, amoxicillin/clavulanate, and ceftriaxone, since most treatments were for acute otitis media.

Of possible high clinical relevance, we found that from 9 to 24 months of age, children with antibiotic exposure had a higher frequency of vaccine-induced antibody levels below protection compared with children with no antibiotic use, placing them at risk of contracting a vaccine-preventable infection for DTaP antigens DT, TT, and PT and for PCV serotype 14.

For time points where antibody levels were determined within 30 days of completion of a course of antibiotics (recent antibiotic use), individual antibiotics were analyzed for effect on antibody levels below protective levels. Across all vaccine antigens measured, we found that all antibiotics had a negative effect on antibody levels and percentage of children achieving the protective antibody level threshold. Amoxicillin use had a lower association with lower antibody levels than the broader spectrum antibiotics, amoxicillin clavulanate (Augmentin), cefdinir, and ceftriaxone. For children receiving amoxicillin/clavulanate prescriptions, it was possible to compare the effect of shorter versus longer courses and we found that a 5-day course was associated with subprotective antibody levels similar to 10 days of amoxicillin, whereas 10-day amoxicillin/clavulanate was associated with higher frequency of children having subprotective antibody levels (Figure).

We examined whether accumulation of antibiotic courses in the first year of life had an association with subsequent vaccine-induced antibody levels and found that each antibiotic prescription was associated with a reduction in the median antibody level. For DTaP, each prescription was associated with 5.8% drop in antibody level to the vaccine components. For Hib the drop was 6.8%, IPV was 11.3%, and PCV was 10.4% – all statistically significant. To determine if booster vaccination influenced this association, a second analysis was performed using antibiotic prescriptions up to 15 months of age. We found each antibiotic prescription was associated with a reduction in median vaccine-induced antibody levels for DTaP by 18%, Hib by 21%, IPV by 19%, and PCV by 12% – all statistically significant.

Our study is the first in young children during the early age window where vaccine-induced immunity is established. Antibiotic use was associated with increased frequency of subprotective antibody levels for several vaccines used in children up to 2 years of age. The lower antibody levels could leave children vulnerable to vaccine preventable diseases. Perhaps outbreaks of vaccine-preventable diseases, such as pertussis, may be a consequence of multiple courses of antibiotics suppressing vaccine-induced immunity.

A goal of this study was to explore potential acute and long-term effects of antibiotic exposure on vaccine-induced antibody levels. Accumulated antibiotic courses up to booster immunization was associated with decreased vaccine antibody levels both before and after booster, suggesting that booster immunization was not sufficient to change the negative association with antibiotic exposure. The results were similar for all vaccines tested, suggesting that the specific vaccine formulation was not a factor.

The study has several limitations. The antibiotic prescription data and measurements of vaccine-induced antibody levels were recorded and measured prospectively; however, our analysis was done retrospectively. The group of study children was derived from my private practice in Rochester, N.Y., and may not be broadly representative of all children. The number of vaccine antibody measurements was limited by serum availability at some sampling time points in some children; and sometimes, the serum samples were collected far apart, which weakened our ability to perform longitudinal analyses. We did not collect stool samples from the children so we could not directly study the effect of antibiotic courses on the gut microbiome.

Our study adds new reasons to be cautious about overprescribing antibiotics on an individual child basis because an adverse effect extends to reduction in vaccine responses. This should be explained to parents requesting unnecessary antibiotics for colds and coughs. When antibiotics are necessary, the judicious choice of a narrow-spectrum antibiotic or a shorter duration of a broader spectrum antibiotic may reduce adverse effects on vaccine-induced immunity.

References

1. Valdez Y et al. Influence of the microbiota on vaccine effectiveness. Trends Immunol. 2014;35(11):526-37.

2. Lynn MA et al. Early-life antibiotic-driven dysbiosis leads to dysregulated vaccine immune responses in mice. Cell Host Microbe. 2018;23(5):653-60.e5.

3. Hagan T et al. Antibiotics-driven gut microbiome perturbation alters immunity to vaccines in humans. Cell. 2019;178(6):1313-28.e13.

4. Chapman T et al. Antibiotic use and vaccine antibody levels. Pediatrics. 2022;149(5);1-17. doi: 10.1542/peds.2021-052061.

In this column I have previously discussed the microbiome and its importance to health, especially as it relates to infections in children. Given the appreciated connection between microbiome and immunity, my group in Rochester, N.Y., recently undertook a study of the effect of antibiotic usage on the immune response to routine early childhood vaccines. In mouse models, it was previously shown that antibiotic exposure induced a reduction in the abundance and diversity of gut microbiota that in turn negatively affected the generation and maintenance of vaccine-induced immunity.^1,2 A study from Stanford University was the first experimental human trial of antibiotic effects on vaccine responses. Adult volunteers were given an antibiotic or not before seasonal influenza vaccination and the researchers identified specific bacteria in the gut that were reduced by the antibiotics given. Those normal bacteria in the gut microbiome were shown to provide positive immunity signals to the systemic immune system that potentiated vaccine responses.³

My group conducted the first-ever study in children to explore whether an association existed between antibiotic use and vaccine-induced antibody levels. In the May issue of Pediatrics we report results from 560 children studied.⁴ From these children, 11,888 serum antibody levels to vaccine antigens were measured. Vaccine-induced antibody levels were determined at various time points after primary vaccination at child age 2, 4, and 6 months and boosters at age 12-18 months for 10 antigens included in four vaccines: DTaP, Hib, IPV, and PCV. The antibody levels to vaccine components were measured to DTaP (diphtheria toxoid, pertussis toxoid, tetanus toxoid, pertactin, and filamentous hemagglutinin), Hib conjugate (polyribosylribitol phosphate), IPV (polio 2), and PCV (serotypes 6B, 14, and 23F). A total of 342 children with 1,678 antibiotic courses prescribed were compared with 218 children with no antibiotic exposures. The predominant antibiotics prescribed were amoxicillin, cefdinir, amoxicillin/clavulanate, and ceftriaxone, since most treatments were for acute otitis media.

Of possible high clinical relevance, we found that from 9 to 24 months of age, children with antibiotic exposure had a higher frequency of vaccine-induced antibody levels below protection compared with children with no antibiotic use, placing them at risk of contracting a vaccine-preventable infection for DTaP antigens DT, TT, and PT and for PCV serotype 14.

For time points where antibody levels were determined within 30 days of completion of a course of antibiotics (recent antibiotic use), individual antibiotics were analyzed for effect on antibody levels below protective levels. Across all vaccine antigens measured, we found that all antibiotics had a negative effect on antibody levels and percentage of children achieving the protective antibody level threshold. Amoxicillin use had a lower association with lower antibody levels than the broader spectrum antibiotics, amoxicillin clavulanate (Augmentin), cefdinir, and ceftriaxone. For children receiving amoxicillin/clavulanate prescriptions, it was possible to compare the effect of shorter versus longer courses and we found that a 5-day course was associated with subprotective antibody levels similar to 10 days of amoxicillin, whereas 10-day amoxicillin/clavulanate was associated with higher frequency of children having subprotective antibody levels (Figure).

We examined whether accumulation of antibiotic courses in the first year of life had an association with subsequent vaccine-induced antibody levels and found that each antibiotic prescription was associated with a reduction in the median antibody level. For DTaP, each prescription was associated with 5.8% drop in antibody level to the vaccine components. For Hib the drop was 6.8%, IPV was 11.3%, and PCV was 10.4% – all statistically significant. To determine if booster vaccination influenced this association, a second analysis was performed using antibiotic prescriptions up to 15 months of age. We found each antibiotic prescription was associated with a reduction in median vaccine-induced antibody levels for DTaP by 18%, Hib by 21%, IPV by 19%, and PCV by 12% – all statistically significant.

Our study is the first in young children during the early age window where vaccine-induced immunity is established. Antibiotic use was associated with increased frequency of subprotective antibody levels for several vaccines used in children up to 2 years of age. The lower antibody levels could leave children vulnerable to vaccine preventable diseases. Perhaps outbreaks of vaccine-preventable diseases, such as pertussis, may be a consequence of multiple courses of antibiotics suppressing vaccine-induced immunity.

A goal of this study was to explore potential acute and long-term effects of antibiotic exposure on vaccine-induced antibody levels. Accumulated antibiotic courses up to booster immunization was associated with decreased vaccine antibody levels both before and after booster, suggesting that booster immunization was not sufficient to change the negative association with antibiotic exposure. The results were similar for all vaccines tested, suggesting that the specific vaccine formulation was not a factor.

The study has several limitations. The antibiotic prescription data and measurements of vaccine-induced antibody levels were recorded and measured prospectively; however, our analysis was done retrospectively. The group of study children was derived from my private practice in Rochester, N.Y., and may not be broadly representative of all children. The number of vaccine antibody measurements was limited by serum availability at some sampling time points in some children; and sometimes, the serum samples were collected far apart, which weakened our ability to perform longitudinal analyses. We did not collect stool samples from the children so we could not directly study the effect of antibiotic courses on the gut microbiome.

Our study adds new reasons to be cautious about overprescribing antibiotics on an individual child basis because an adverse effect extends to reduction in vaccine responses. This should be explained to parents requesting unnecessary antibiotics for colds and coughs. When antibiotics are necessary, the judicious choice of a narrow-spectrum antibiotic or a shorter duration of a broader spectrum antibiotic may reduce adverse effects on vaccine-induced immunity.

References

1. Valdez Y et al. Influence of the microbiota on vaccine effectiveness. Trends Immunol. 2014;35(11):526-37.

2. Lynn MA et al. Early-life antibiotic-driven dysbiosis leads to dysregulated vaccine immune responses in mice. Cell Host Microbe. 2018;23(5):653-60.e5.

3. Hagan T et al. Antibiotics-driven gut microbiome perturbation alters immunity to vaccines in humans. Cell. 2019;178(6):1313-28.e13.

4. Chapman T et al. Antibiotic use and vaccine antibody levels. Pediatrics. 2022;149(5);1-17. doi: 10.1542/peds.2021-052061.

In this column I have previously discussed the microbiome and its importance to health, especially as it relates to infections in children. Given the appreciated connection between microbiome and immunity, my group in Rochester, N.Y., recently undertook a study of the effect of antibiotic usage on the immune response to routine early childhood vaccines. In mouse models, it was previously shown that antibiotic exposure induced a reduction in the abundance and diversity of gut microbiota that in turn negatively affected the generation and maintenance of vaccine-induced immunity.^1,2 A study from Stanford University was the first experimental human trial of antibiotic effects on vaccine responses. Adult volunteers were given an antibiotic or not before seasonal influenza vaccination and the researchers identified specific bacteria in the gut that were reduced by the antibiotics given. Those normal bacteria in the gut microbiome were shown to provide positive immunity signals to the systemic immune system that potentiated vaccine responses.³

My group conducted the first-ever study in children to explore whether an association existed between antibiotic use and vaccine-induced antibody levels. In the May issue of Pediatrics we report results from 560 children studied.⁴ From these children, 11,888 serum antibody levels to vaccine antigens were measured. Vaccine-induced antibody levels were determined at various time points after primary vaccination at child age 2, 4, and 6 months and boosters at age 12-18 months for 10 antigens included in four vaccines: DTaP, Hib, IPV, and PCV. The antibody levels to vaccine components were measured to DTaP (diphtheria toxoid, pertussis toxoid, tetanus toxoid, pertactin, and filamentous hemagglutinin), Hib conjugate (polyribosylribitol phosphate), IPV (polio 2), and PCV (serotypes 6B, 14, and 23F). A total of 342 children with 1,678 antibiotic courses prescribed were compared with 218 children with no antibiotic exposures. The predominant antibiotics prescribed were amoxicillin, cefdinir, amoxicillin/clavulanate, and ceftriaxone, since most treatments were for acute otitis media.

Of possible high clinical relevance, we found that from 9 to 24 months of age, children with antibiotic exposure had a higher frequency of vaccine-induced antibody levels below protection compared with children with no antibiotic use, placing them at risk of contracting a vaccine-preventable infection for DTaP antigens DT, TT, and PT and for PCV serotype 14.

For time points where antibody levels were determined within 30 days of completion of a course of antibiotics (recent antibiotic use), individual antibiotics were analyzed for effect on antibody levels below protective levels. Across all vaccine antigens measured, we found that all antibiotics had a negative effect on antibody levels and percentage of children achieving the protective antibody level threshold. Amoxicillin use had a lower association with lower antibody levels than the broader spectrum antibiotics, amoxicillin clavulanate (Augmentin), cefdinir, and ceftriaxone. For children receiving amoxicillin/clavulanate prescriptions, it was possible to compare the effect of shorter versus longer courses and we found that a 5-day course was associated with subprotective antibody levels similar to 10 days of amoxicillin, whereas 10-day amoxicillin/clavulanate was associated with higher frequency of children having subprotective antibody levels (Figure).

We examined whether accumulation of antibiotic courses in the first year of life had an association with subsequent vaccine-induced antibody levels and found that each antibiotic prescription was associated with a reduction in the median antibody level. For DTaP, each prescription was associated with 5.8% drop in antibody level to the vaccine components. For Hib the drop was 6.8%, IPV was 11.3%, and PCV was 10.4% – all statistically significant. To determine if booster vaccination influenced this association, a second analysis was performed using antibiotic prescriptions up to 15 months of age. We found each antibiotic prescription was associated with a reduction in median vaccine-induced antibody levels for DTaP by 18%, Hib by 21%, IPV by 19%, and PCV by 12% – all statistically significant.

Our study is the first in young children during the early age window where vaccine-induced immunity is established. Antibiotic use was associated with increased frequency of subprotective antibody levels for several vaccines used in children up to 2 years of age. The lower antibody levels could leave children vulnerable to vaccine preventable diseases. Perhaps outbreaks of vaccine-preventable diseases, such as pertussis, may be a consequence of multiple courses of antibiotics suppressing vaccine-induced immunity.

A goal of this study was to explore potential acute and long-term effects of antibiotic exposure on vaccine-induced antibody levels. Accumulated antibiotic courses up to booster immunization was associated with decreased vaccine antibody levels both before and after booster, suggesting that booster immunization was not sufficient to change the negative association with antibiotic exposure. The results were similar for all vaccines tested, suggesting that the specific vaccine formulation was not a factor.

The study has several limitations. The antibiotic prescription data and measurements of vaccine-induced antibody levels were recorded and measured prospectively; however, our analysis was done retrospectively. The group of study children was derived from my private practice in Rochester, N.Y., and may not be broadly representative of all children. The number of vaccine antibody measurements was limited by serum availability at some sampling time points in some children; and sometimes, the serum samples were collected far apart, which weakened our ability to perform longitudinal analyses. We did not collect stool samples from the children so we could not directly study the effect of antibiotic courses on the gut microbiome.

Our study adds new reasons to be cautious about overprescribing antibiotics on an individual child basis because an adverse effect extends to reduction in vaccine responses. This should be explained to parents requesting unnecessary antibiotics for colds and coughs. When antibiotics are necessary, the judicious choice of a narrow-spectrum antibiotic or a shorter duration of a broader spectrum antibiotic may reduce adverse effects on vaccine-induced immunity.

References

1. Valdez Y et al. Influence of the microbiota on vaccine effectiveness. Trends Immunol. 2014;35(11):526-37.

2. Lynn MA et al. Early-life antibiotic-driven dysbiosis leads to dysregulated vaccine immune responses in mice. Cell Host Microbe. 2018;23(5):653-60.e5.

3. Hagan T et al. Antibiotics-driven gut microbiome perturbation alters immunity to vaccines in humans. Cell. 2019;178(6):1313-28.e13.

4. Chapman T et al. Antibiotic use and vaccine antibody levels. Pediatrics. 2022;149(5);1-17. doi: 10.1542/peds.2021-052061.

A 6-month-old boy presented with 2 days of looser-than-normal stools without blood or mucous. Before the onset of diarrhea, he had been fed at least two bottles of an infant formula identified in a national recall. His mom requested testing for Cronobacter sakazakii.

In mid-February, Abbott Nutrition recalled specific lots of powdered formula produced at one Michigan manufacturing facility because of possible Cronobacter contamination. To date, a public health investigation has identified four infants in three states who developed Cronobacter infection after consuming formula that was part of the recall. Two of the infants died.

As media reports urged families to search their kitchens for containers of the implicated formula and return them for a refund, worried parents reached out to pediatric care providers for advice.

Cronobacter sakazakii and other Cronobacter species are Gram-negative environmental organisms that occasionally cause bacteremia and meningitis in young infants. Although these infections are not subject to mandatory reporting in most states, laboratory-based surveillance suggests that 18 cases occur annually in the United States (0.49 cases/100,00 infants).

While early reports in the literature described cases in hospitalized, preterm infants, infections also occur in the community and in children born at or near term. A Centers for Disease Control and Prevention review of domestic and international cases identified 183 children <12 months of age between 1961 and 2018 described as diagnosed with Cronobacter bacteremia or meningitis.¹ Of the 79 U.S. cases, 34 occurred in term infants and 50 were community onset. Most cases occurred in the first month of life; the oldest child was 35 days of age at the onset of symptoms. Meningitis was more likely in infants born close to term and who were not hospitalized at the time of infection. The majority of infants for whom a feeding history was available had consumed powdered formula.

Back in the exam room, the 6-month-old was examined and found to be vigorous and well-appearing with normal vital signs and no signs of dehydration. The infant’s pediatrician found no clinical indication to perform a blood culture or lumbar puncture, the tests used to diagnose invasive Cronobacter infection. She explained that stool cultures are not recommended, as Cronobacter does not usually cause diarrhea in infants and finding the bacteria in the stool may represent colonization rather than infection.

The pediatrician did take the opportunity to talk to the mom about her formula preparation practices and shared a handout. Powdered formula isn’t sterile, but it is safe for most infants when prepared according to manufacturer’s directions. Contamination of formula during or after preparation can also result in Cronobacter infection in vulnerable infants.

The mom was surprised – and unhappy – to learn that Cronobacter could be lurking in her kitchen. More than a decade ago, investigators visited 78 households in Tennessee and cultured multiple kitchen surfaces.²C. sakazakii was recovered from 21 homes. Most of the positive cultures were from sinks, counter tops, and used dishcloths. Cronobacter has also been cultured from a variety of dried food items, including powdered milk, herbal tea, and starches.

According to the CDC, liquid formula, a product that is sterile until opened, is a safer choice for formula-fed infants who are less than 3 months of age, were born prematurely, or have a compromised immune system. When these infants must be fed powdered formula, preparing it with water heated to at least 158°F or 70°C can kill Cronobacter organisms. Parents should be instructed to boil water and let it cool for about 5 minutes before using it to mix formula.

While most cases of Cronobacter in infants have been epidemiologically linked to consumption of powdered formula, sporadic case reports describe infection in infants fed expressed breast milk. In one report, identical bacterial isolates were recovered from expressed milk fed to an infected infant and the breast pump used to express the milk.³

Moms who express milk should be instructed in proper breast pump hygiene, including washing hands thoroughly before handling breast pumps; disassembling and cleaning breast pumps kits after each use, either in hot soapy water with a dedicated brush and basin or in the dishwasher; air drying on a clean surface; and sanitizing at least daily by boiling, steaming, or using a dishwasher’s sanitize cycle.

Health care providers are encouraged to report Cronobacter cases to their state or local health departments.

Dr. Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.

References

1. Strysko J et al. Emerg Infect Dis. 2020;26(5):857-65.

2. Kilonzo-Nthenge A et al. J Food Protect 2012;75(8):1512-7.

3. Bowen A et al. MMWR Morb Mortal Wkly Rep. 2017;66:761-2.

A 6-month-old boy presented with 2 days of looser-than-normal stools without blood or mucous. Before the onset of diarrhea, he had been fed at least two bottles of an infant formula identified in a national recall. His mom requested testing for Cronobacter sakazakii.

In mid-February, Abbott Nutrition recalled specific lots of powdered formula produced at one Michigan manufacturing facility because of possible Cronobacter contamination. To date, a public health investigation has identified four infants in three states who developed Cronobacter infection after consuming formula that was part of the recall. Two of the infants died.

As media reports urged families to search their kitchens for containers of the implicated formula and return them for a refund, worried parents reached out to pediatric care providers for advice.

Cronobacter sakazakii and other Cronobacter species are Gram-negative environmental organisms that occasionally cause bacteremia and meningitis in young infants. Although these infections are not subject to mandatory reporting in most states, laboratory-based surveillance suggests that 18 cases occur annually in the United States (0.49 cases/100,00 infants).

While early reports in the literature described cases in hospitalized, preterm infants, infections also occur in the community and in children born at or near term. A Centers for Disease Control and Prevention review of domestic and international cases identified 183 children <12 months of age between 1961 and 2018 described as diagnosed with Cronobacter bacteremia or meningitis.¹ Of the 79 U.S. cases, 34 occurred in term infants and 50 were community onset. Most cases occurred in the first month of life; the oldest child was 35 days of age at the onset of symptoms. Meningitis was more likely in infants born close to term and who were not hospitalized at the time of infection. The majority of infants for whom a feeding history was available had consumed powdered formula.

Back in the exam room, the 6-month-old was examined and found to be vigorous and well-appearing with normal vital signs and no signs of dehydration. The infant’s pediatrician found no clinical indication to perform a blood culture or lumbar puncture, the tests used to diagnose invasive Cronobacter infection. She explained that stool cultures are not recommended, as Cronobacter does not usually cause diarrhea in infants and finding the bacteria in the stool may represent colonization rather than infection.

The pediatrician did take the opportunity to talk to the mom about her formula preparation practices and shared a handout. Powdered formula isn’t sterile, but it is safe for most infants when prepared according to manufacturer’s directions. Contamination of formula during or after preparation can also result in Cronobacter infection in vulnerable infants.

The mom was surprised – and unhappy – to learn that Cronobacter could be lurking in her kitchen. More than a decade ago, investigators visited 78 households in Tennessee and cultured multiple kitchen surfaces.²C. sakazakii was recovered from 21 homes. Most of the positive cultures were from sinks, counter tops, and used dishcloths. Cronobacter has also been cultured from a variety of dried food items, including powdered milk, herbal tea, and starches.

According to the CDC, liquid formula, a product that is sterile until opened, is a safer choice for formula-fed infants who are less than 3 months of age, were born prematurely, or have a compromised immune system. When these infants must be fed powdered formula, preparing it with water heated to at least 158°F or 70°C can kill Cronobacter organisms. Parents should be instructed to boil water and let it cool for about 5 minutes before using it to mix formula.

While most cases of Cronobacter in infants have been epidemiologically linked to consumption of powdered formula, sporadic case reports describe infection in infants fed expressed breast milk. In one report, identical bacterial isolates were recovered from expressed milk fed to an infected infant and the breast pump used to express the milk.³

Moms who express milk should be instructed in proper breast pump hygiene, including washing hands thoroughly before handling breast pumps; disassembling and cleaning breast pumps kits after each use, either in hot soapy water with a dedicated brush and basin or in the dishwasher; air drying on a clean surface; and sanitizing at least daily by boiling, steaming, or using a dishwasher’s sanitize cycle.

Health care providers are encouraged to report Cronobacter cases to their state or local health departments.

Dr. Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.

References

1. Strysko J et al. Emerg Infect Dis. 2020;26(5):857-65.

2. Kilonzo-Nthenge A et al. J Food Protect 2012;75(8):1512-7.

3. Bowen A et al. MMWR Morb Mortal Wkly Rep. 2017;66:761-2.

A 6-month-old boy presented with 2 days of looser-than-normal stools without blood or mucous. Before the onset of diarrhea, he had been fed at least two bottles of an infant formula identified in a national recall. His mom requested testing for Cronobacter sakazakii.

In mid-February, Abbott Nutrition recalled specific lots of powdered formula produced at one Michigan manufacturing facility because of possible Cronobacter contamination. To date, a public health investigation has identified four infants in three states who developed Cronobacter infection after consuming formula that was part of the recall. Two of the infants died.

As media reports urged families to search their kitchens for containers of the implicated formula and return them for a refund, worried parents reached out to pediatric care providers for advice.

Cronobacter sakazakii and other Cronobacter species are Gram-negative environmental organisms that occasionally cause bacteremia and meningitis in young infants. Although these infections are not subject to mandatory reporting in most states, laboratory-based surveillance suggests that 18 cases occur annually in the United States (0.49 cases/100,00 infants).

While early reports in the literature described cases in hospitalized, preterm infants, infections also occur in the community and in children born at or near term. A Centers for Disease Control and Prevention review of domestic and international cases identified 183 children <12 months of age between 1961 and 2018 described as diagnosed with Cronobacter bacteremia or meningitis.¹ Of the 79 U.S. cases, 34 occurred in term infants and 50 were community onset. Most cases occurred in the first month of life; the oldest child was 35 days of age at the onset of symptoms. Meningitis was more likely in infants born close to term and who were not hospitalized at the time of infection. The majority of infants for whom a feeding history was available had consumed powdered formula.

Back in the exam room, the 6-month-old was examined and found to be vigorous and well-appearing with normal vital signs and no signs of dehydration. The infant’s pediatrician found no clinical indication to perform a blood culture or lumbar puncture, the tests used to diagnose invasive Cronobacter infection. She explained that stool cultures are not recommended, as Cronobacter does not usually cause diarrhea in infants and finding the bacteria in the stool may represent colonization rather than infection.

The pediatrician did take the opportunity to talk to the mom about her formula preparation practices and shared a handout. Powdered formula isn’t sterile, but it is safe for most infants when prepared according to manufacturer’s directions. Contamination of formula during or after preparation can also result in Cronobacter infection in vulnerable infants.

The mom was surprised – and unhappy – to learn that Cronobacter could be lurking in her kitchen. More than a decade ago, investigators visited 78 households in Tennessee and cultured multiple kitchen surfaces.²C. sakazakii was recovered from 21 homes. Most of the positive cultures were from sinks, counter tops, and used dishcloths. Cronobacter has also been cultured from a variety of dried food items, including powdered milk, herbal tea, and starches.

According to the CDC, liquid formula, a product that is sterile until opened, is a safer choice for formula-fed infants who are less than 3 months of age, were born prematurely, or have a compromised immune system. When these infants must be fed powdered formula, preparing it with water heated to at least 158°F or 70°C can kill Cronobacter organisms. Parents should be instructed to boil water and let it cool for about 5 minutes before using it to mix formula.

While most cases of Cronobacter in infants have been epidemiologically linked to consumption of powdered formula, sporadic case reports describe infection in infants fed expressed breast milk. In one report, identical bacterial isolates were recovered from expressed milk fed to an infected infant and the breast pump used to express the milk.³

Moms who express milk should be instructed in proper breast pump hygiene, including washing hands thoroughly before handling breast pumps; disassembling and cleaning breast pumps kits after each use, either in hot soapy water with a dedicated brush and basin or in the dishwasher; air drying on a clean surface; and sanitizing at least daily by boiling, steaming, or using a dishwasher’s sanitize cycle.

Health care providers are encouraged to report Cronobacter cases to their state or local health departments.

Dr. Bryant is a pediatrician specializing in infectious diseases at the University of Louisville (Ky.) and Norton Children’s Hospital, also in Louisville. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.

References

1. Strysko J et al. Emerg Infect Dis. 2020;26(5):857-65.

2. Kilonzo-Nthenge A et al. J Food Protect 2012;75(8):1512-7.

3. Bowen A et al. MMWR Morb Mortal Wkly Rep. 2017;66:761-2.

Twenty years ago, the dilemma in treating acute otitis media (AOM) was which among 10-plus antibiotics to prescribe. A recent column discussed the evolving pathogen distribution in AOM and its effects on antibiotic choices.¹ But here we consider treatment duration. Until the past decade, AOM treatment (except azithromycin) involved 10-day courses. But lately, 10-day antibiotic regimens for uncomplicated infections are disappearing. Shorter-course recommendations are the new norm because of the evolving clinical data showing that an appropriately chosen antibiotic (in partnership with host defenses and source control) resolves infection faster than was previously thought. Shorter courses make sense because of fewer adverse effects, less distortion of normal flora, and less likely induction of pathogen resistance. Table 4.12 in the newest 2021-2024 SOID Redbook lists three antibiotic durations for AOM, and actually there are more than that.

Why so many duration options? Clinical data show that not all AOM is alike and short courses work for subsets of AOM because, besides antibiotics, key elements in AOM resolution are host anatomy and immunity. Bacterial AOM results from a combination of refluxed pathogens in the middle ear being trapped when the eustachian tube malfunctions (infection occurs when middle ear plumbing gets stopped up). If the eustachian tube spontaneously drains and the host immune response slows/stops pathogen growth, no antibiotics are needed. Indeed, a sizable proportion of mild/moderate AOM episodes spontaneously resolve, particularly in children over 2 years old. So a high likelihood of spontaneous remission allows an initial 0-days duration option (watchful waiting) or delayed antibiotics (rescue prescriptions) for older children.

That said, when one chooses to initially prescribe antibiotics for AOM, different durations are recommended. Table 1 has my suggestions.

Data that gave me better microbiological understanding of why oral AOM trials less than 10 days were successful involved purulent AOM drainage from children who had pressure-equalizing (PE) tubes.² The authors randomized children to either standard-dose amoxicillin-clavulanate or placebo. Of note, 95% of pathogens were susceptible to the antibiotic; 5% were pneumococcus intermediately resistant to penicillin. The authors sampled ear drainage daily for 7 days. Figure 1 shows that cultures remained positive in only around 5% of children by day 3-5 of antibiotics, but viable bacteria persisted through 7 days in over half of placebo recipients. Remember, both groups benefited from a form of source control (drainage of the middle ear via PE tubes). So, if antibiotics can do the job in 3-5 days, why continue antibiotics beyond 5 days?

Anatomy and severity. In children over 5 years old (reasonably mature eustachian tube anatomy) with nonrecurrent (no AOM in past month), nonsevere (no otalgia or high fever) AOM, 5 days is enough. But 2- to 5-year-olds (less mature anatomy) need 7 days and those <2 years old (least mature plumbing) need 10 days. Likewise, severe AOM usually warrants 10 days. Some experts recommend 10 days for bilateral AOM as well.

These age/severity differences make sense because failures are more frequent with:

1. Younger age.³ While not proven, my hypothesis is that “natural” source control (spontaneous internal draining the middle ear into the nasopharynx [NP]) is less frequent in younger children because they have less mature eustachian tube systems. Further, reflux of persisting NP organisms could restart a new AOM episode even if the original pathogen was eliminated by a short 5-day course.

2. Severe AOM. A rationale for longer courses in severe AOM (ear pain, high fever) is that high middle-ear pressures (indicated by degree of tympanic membrane bulging and ear pain) could impede antibiotic penetration, or that high initial bacterial loads (perhaps indicated by systemic fever) require more antibiotic. And finally, return to baseline eustachian tube function may take longer if severe AOM caused enhanced inflammation.

3. Recurrent AOM. (AOM within 1 prior month) – With recurrent AOM, the second “hit” to the eustachian tube may lead to more dysfunction, so a longer antibiotic course may be required to allow more complete source control and more time for more complete functional recovery after a repeated inflammatory injury.

4. Bilateral AOM. Two independent but infected sites mean twice the chance for failure. So, a longer course could allow more time for both sites to undergo “natural” source control.⁴

More bacteria – more antibiotic? So, is more antibiotic really needed for a higher bacterial load? In vitro this is known as the “inoculum effect,” particularly for beta-lactam drugs, for example, amoxicillin and cephalosporins. Laboratory susceptibility testing is performed with a specifically defined quantity of bacteria (10⁵ bacteria/mL) and the minimum inhibitory concentration (MIC) is the lowest antibiotic concentration that stops bacterial growth. We know that drugs will likely fail if the MIC exceeds the achievable antibiotic concentration at the infection site. But is it as simple as just exceeding the MIC at the infection site? No, pharmacodynamics tell us that overall antibiotic exposure is also important. For example, to be successful, beta-lactam concentrations need to be above the MIC for 40%-50% of the day.

Dr. Christopher J. Harrison is professor of pediatrics and pediatric infectious diseases at Children’s Mercy Hospitals and Clinics in Kansas City, Mo. Email him at pdnews@mdedge.com.

References

1. Pichichero ME. MDedge. 2022 Jan 11.

2. Ruohola A et al. Pediatrics. 2003;111(5):1061-7.

3. Hoberman A et al. N Engl J Med. 2016;375(25):2446-56.

4. Pichichero ME et al. Otolaryngol Head Neck Surg. 2001;124(4):381-7.

5. Harrison CJ et al. Pediatr Infect Dis. 1985;4(6):641-6.

6. Leibovitz E et al. Pediatr Infect Dis. 2000;19(11):1040-5.

Twenty years ago, the dilemma in treating acute otitis media (AOM) was which among 10-plus antibiotics to prescribe. A recent column discussed the evolving pathogen distribution in AOM and its effects on antibiotic choices.¹ But here we consider treatment duration. Until the past decade, AOM treatment (except azithromycin) involved 10-day courses. But lately, 10-day antibiotic regimens for uncomplicated infections are disappearing. Shorter-course recommendations are the new norm because of the evolving clinical data showing that an appropriately chosen antibiotic (in partnership with host defenses and source control) resolves infection faster than was previously thought. Shorter courses make sense because of fewer adverse effects, less distortion of normal flora, and less likely induction of pathogen resistance. Table 4.12 in the newest 2021-2024 SOID Redbook lists three antibiotic durations for AOM, and actually there are more than that.

Why so many duration options? Clinical data show that not all AOM is alike and short courses work for subsets of AOM because, besides antibiotics, key elements in AOM resolution are host anatomy and immunity. Bacterial AOM results from a combination of refluxed pathogens in the middle ear being trapped when the eustachian tube malfunctions (infection occurs when middle ear plumbing gets stopped up). If the eustachian tube spontaneously drains and the host immune response slows/stops pathogen growth, no antibiotics are needed. Indeed, a sizable proportion of mild/moderate AOM episodes spontaneously resolve, particularly in children over 2 years old. So a high likelihood of spontaneous remission allows an initial 0-days duration option (watchful waiting) or delayed antibiotics (rescue prescriptions) for older children.

That said, when one chooses to initially prescribe antibiotics for AOM, different durations are recommended. Table 1 has my suggestions.

Data that gave me better microbiological understanding of why oral AOM trials less than 10 days were successful involved purulent AOM drainage from children who had pressure-equalizing (PE) tubes.² The authors randomized children to either standard-dose amoxicillin-clavulanate or placebo. Of note, 95% of pathogens were susceptible to the antibiotic; 5% were pneumococcus intermediately resistant to penicillin. The authors sampled ear drainage daily for 7 days. Figure 1 shows that cultures remained positive in only around 5% of children by day 3-5 of antibiotics, but viable bacteria persisted through 7 days in over half of placebo recipients. Remember, both groups benefited from a form of source control (drainage of the middle ear via PE tubes). So, if antibiotics can do the job in 3-5 days, why continue antibiotics beyond 5 days?

Anatomy and severity. In children over 5 years old (reasonably mature eustachian tube anatomy) with nonrecurrent (no AOM in past month), nonsevere (no otalgia or high fever) AOM, 5 days is enough. But 2- to 5-year-olds (less mature anatomy) need 7 days and those <2 years old (least mature plumbing) need 10 days. Likewise, severe AOM usually warrants 10 days. Some experts recommend 10 days for bilateral AOM as well.

These age/severity differences make sense because failures are more frequent with:

1. Younger age.³ While not proven, my hypothesis is that “natural” source control (spontaneous internal draining the middle ear into the nasopharynx [NP]) is less frequent in younger children because they have less mature eustachian tube systems. Further, reflux of persisting NP organisms could restart a new AOM episode even if the original pathogen was eliminated by a short 5-day course.

2. Severe AOM. A rationale for longer courses in severe AOM (ear pain, high fever) is that high middle-ear pressures (indicated by degree of tympanic membrane bulging and ear pain) could impede antibiotic penetration, or that high initial bacterial loads (perhaps indicated by systemic fever) require more antibiotic. And finally, return to baseline eustachian tube function may take longer if severe AOM caused enhanced inflammation.

3. Recurrent AOM. (AOM within 1 prior month) – With recurrent AOM, the second “hit” to the eustachian tube may lead to more dysfunction, so a longer antibiotic course may be required to allow more complete source control and more time for more complete functional recovery after a repeated inflammatory injury.

4. Bilateral AOM. Two independent but infected sites mean twice the chance for failure. So, a longer course could allow more time for both sites to undergo “natural” source control.⁴

More bacteria – more antibiotic? So, is more antibiotic really needed for a higher bacterial load? In vitro this is known as the “inoculum effect,” particularly for beta-lactam drugs, for example, amoxicillin and cephalosporins. Laboratory susceptibility testing is performed with a specifically defined quantity of bacteria (10⁵ bacteria/mL) and the minimum inhibitory concentration (MIC) is the lowest antibiotic concentration that stops bacterial growth. We know that drugs will likely fail if the MIC exceeds the achievable antibiotic concentration at the infection site. But is it as simple as just exceeding the MIC at the infection site? No, pharmacodynamics tell us that overall antibiotic exposure is also important. For example, to be successful, beta-lactam concentrations need to be above the MIC for 40%-50% of the day.

Dr. Christopher J. Harrison is professor of pediatrics and pediatric infectious diseases at Children’s Mercy Hospitals and Clinics in Kansas City, Mo. Email him at pdnews@mdedge.com.

References

1. Pichichero ME. MDedge. 2022 Jan 11.

2. Ruohola A et al. Pediatrics. 2003;111(5):1061-7.

3. Hoberman A et al. N Engl J Med. 2016;375(25):2446-56.

4. Pichichero ME et al. Otolaryngol Head Neck Surg. 2001;124(4):381-7.

5. Harrison CJ et al. Pediatr Infect Dis. 1985;4(6):641-6.

6. Leibovitz E et al. Pediatr Infect Dis. 2000;19(11):1040-5.

Twenty years ago, the dilemma in treating acute otitis media (AOM) was which among 10-plus antibiotics to prescribe. A recent column discussed the evolving pathogen distribution in AOM and its effects on antibiotic choices.¹ But here we consider treatment duration. Until the past decade, AOM treatment (except azithromycin) involved 10-day courses. But lately, 10-day antibiotic regimens for uncomplicated infections are disappearing. Shorter-course recommendations are the new norm because of the evolving clinical data showing that an appropriately chosen antibiotic (in partnership with host defenses and source control) resolves infection faster than was previously thought. Shorter courses make sense because of fewer adverse effects, less distortion of normal flora, and less likely induction of pathogen resistance. Table 4.12 in the newest 2021-2024 SOID Redbook lists three antibiotic durations for AOM, and actually there are more than that.

Why so many duration options? Clinical data show that not all AOM is alike and short courses work for subsets of AOM because, besides antibiotics, key elements in AOM resolution are host anatomy and immunity. Bacterial AOM results from a combination of refluxed pathogens in the middle ear being trapped when the eustachian tube malfunctions (infection occurs when middle ear plumbing gets stopped up). If the eustachian tube spontaneously drains and the host immune response slows/stops pathogen growth, no antibiotics are needed. Indeed, a sizable proportion of mild/moderate AOM episodes spontaneously resolve, particularly in children over 2 years old. So a high likelihood of spontaneous remission allows an initial 0-days duration option (watchful waiting) or delayed antibiotics (rescue prescriptions) for older children.

That said, when one chooses to initially prescribe antibiotics for AOM, different durations are recommended. Table 1 has my suggestions.

Data that gave me better microbiological understanding of why oral AOM trials less than 10 days were successful involved purulent AOM drainage from children who had pressure-equalizing (PE) tubes.² The authors randomized children to either standard-dose amoxicillin-clavulanate or placebo. Of note, 95% of pathogens were susceptible to the antibiotic; 5% were pneumococcus intermediately resistant to penicillin. The authors sampled ear drainage daily for 7 days. Figure 1 shows that cultures remained positive in only around 5% of children by day 3-5 of antibiotics, but viable bacteria persisted through 7 days in over half of placebo recipients. Remember, both groups benefited from a form of source control (drainage of the middle ear via PE tubes). So, if antibiotics can do the job in 3-5 days, why continue antibiotics beyond 5 days?

Anatomy and severity. In children over 5 years old (reasonably mature eustachian tube anatomy) with nonrecurrent (no AOM in past month), nonsevere (no otalgia or high fever) AOM, 5 days is enough. But 2- to 5-year-olds (less mature anatomy) need 7 days and those <2 years old (least mature plumbing) need 10 days. Likewise, severe AOM usually warrants 10 days. Some experts recommend 10 days for bilateral AOM as well.

These age/severity differences make sense because failures are more frequent with:

1. Younger age.³ While not proven, my hypothesis is that “natural” source control (spontaneous internal draining the middle ear into the nasopharynx [NP]) is less frequent in younger children because they have less mature eustachian tube systems. Further, reflux of persisting NP organisms could restart a new AOM episode even if the original pathogen was eliminated by a short 5-day course.

2. Severe AOM. A rationale for longer courses in severe AOM (ear pain, high fever) is that high middle-ear pressures (indicated by degree of tympanic membrane bulging and ear pain) could impede antibiotic penetration, or that high initial bacterial loads (perhaps indicated by systemic fever) require more antibiotic. And finally, return to baseline eustachian tube function may take longer if severe AOM caused enhanced inflammation.

3. Recurrent AOM. (AOM within 1 prior month) – With recurrent AOM, the second “hit” to the eustachian tube may lead to more dysfunction, so a longer antibiotic course may be required to allow more complete source control and more time for more complete functional recovery after a repeated inflammatory injury.

4. Bilateral AOM. Two independent but infected sites mean twice the chance for failure. So, a longer course could allow more time for both sites to undergo “natural” source control.⁴

More bacteria – more antibiotic? So, is more antibiotic really needed for a higher bacterial load? In vitro this is known as the “inoculum effect,” particularly for beta-lactam drugs, for example, amoxicillin and cephalosporins. Laboratory susceptibility testing is performed with a specifically defined quantity of bacteria (10⁵ bacteria/mL) and the minimum inhibitory concentration (MIC) is the lowest antibiotic concentration that stops bacterial growth. We know that drugs will likely fail if the MIC exceeds the achievable antibiotic concentration at the infection site. But is it as simple as just exceeding the MIC at the infection site? No, pharmacodynamics tell us that overall antibiotic exposure is also important. For example, to be successful, beta-lactam concentrations need to be above the MIC for 40%-50% of the day.

Dr. Christopher J. Harrison is professor of pediatrics and pediatric infectious diseases at Children’s Mercy Hospitals and Clinics in Kansas City, Mo. Email him at pdnews@mdedge.com.

References

1. Pichichero ME. MDedge. 2022 Jan 11.

2. Ruohola A et al. Pediatrics. 2003;111(5):1061-7.

3. Hoberman A et al. N Engl J Med. 2016;375(25):2446-56.

4. Pichichero ME et al. Otolaryngol Head Neck Surg. 2001;124(4):381-7.

5. Harrison CJ et al. Pediatr Infect Dis. 1985;4(6):641-6.

6. Leibovitz E et al. Pediatr Infect Dis. 2000;19(11):1040-5.