Health care workers directly caring for patients with Middle East respiratory syndrome coronavirus (MERS-CoV) are more highly predisposed to contracting the virus, but in a milder form than that of their patients, thus making it difficult to diagnose and treat.
In a study published in Emerging Infectious Diseases, health care professionals (HCP) from the King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia, were examined to determine their likelihood for getting MERS-CoV based on their proximity to patients who already had it.
Courtesy CDC; Maureen Metcalfe and Azaibi Tamin
“Healthcare settings are important amplifiers of transmission,” explained the investigators, led by Basem M. Alraddadi, MD. “Current MERS-CoV infection control recommendations are based on experience with other viruses rather than on a complete understanding of the epidemiology of MERS-CoV transmission.”
Dr. Alraddadi and his coinvestigators identified 363 HCP, all of whom would be placed into one of three cohorts based on the department in which they worked most extensively: the Medical Intensive Care Unit (MICU), the emergency department (ED), and the neurology unit. A total of 292 HCP were ultimately enrolled in the study: 131 in MICU, 127 in ED, and 34 in neurology. After 9 subjects were excluded because of unavailability of serum specimens, 128 MICU, 122 ED, and 33 neurology unit workers remained.
While none of the neurology unit workers contracted the virus, 15 MICU workers (11.7%) and 5 ED workers (4.1%) did, for a total of 20 out of the 250 subjects in those two cohorts (8%). Radiology technicians were the most susceptible, as 5 of 17 (29.4%) got the virus, followed by 13 of 138 nurses (9.4%), 1 of 31 respiratory therapists (3.2%), and 1 of 41 physicians (2.4%).
“HCP who reported always covering their nose and mouth with either a medical mask or N95 respirator had lower risk for infection than did HCP reporting not always or never doing so, [while] those who reported always using N95 respirators for direct patient contact were less likely to be seropositive, a trend that approached statistical significance (P = .07),” the authors noted.
The most frequent symptoms reported by those surveyed were muscle pain, fevers, headaches, dry cough, and shortness of breath. In the 20-case HCP sample, however, 12 subjects (60%) only had mild illness while 3 (15%) were asymptomatic, making it very hard to diagnose and treat their infection. Three subjects (15%) had severe illness, while another two (10%) had moderate illness, meaning they were admitted to hospital but did not require any mechanical ventilation.
“Our study did not identify strong associations with underlying chronic illnesses, most likely because the prevalence of such conditions was low ([less than] 10%) in this population, [but] HCPs with a history of smoking had a risk for infection almost 3 times that of nonsmokers,” the authors wrote (Emerg Infect Dis. 2016 Nov. doi: 10.3201/eid2211.160920).
The Ministry of Health of Saudi Arabia and the Centers for Disease Control and Prevention funded the study. Dr. Alraddadi and his coauthors did not report any disclosures.