Each year in the United States, more than 2 million people contract drug-resistant infections and 23,000 die, primarily in a hospital setting. The figures are part of a first-of-its-kind report from the Centers for Disease Control and Prevention, detailing in actual numbers the extent of the nation’s growing antibiotic crisis.
"One of the reasons we’re issuing the report now is that it is not too late. If we’re not careful, the medicine chest will be empty when we go there to look for a life-saving antibiotic for a deadly infection. But if we act now, we can preserve these medications, while we work on the development of new medications," Dr. Thomas R. Frieden, the CDC’s director, said in a media briefing.
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Dr. Thomas Frieden
Noting that the numbers are only "bare minimum, very conservative estimates," Dr. Frieden said that many infections are resistant to more than just one medication and that for health care-associated infections, some cases are still unaccounted for in nonhospital settings such as nursing homes and dialysis facilities.
Of particular concern, according to the report, is Clostridium difficile, because its annual death toll of an estimated 14,000, accounts for more than half of all deaths from drug-resistant infection. This is the case even though C. difficile is a bacterium that – although it is not particularly resistant to treatment – is made stronger when antibiotics are used to treat other infections.
The public health threat, as delineated in the report, is tertiary. The first level is "urgent" and includes C. difficile, carbapenem-resistant Enterobacteriaceae, and drug-resistant Neisseria gonorrhoeae for fear of it developing cephalosporin resistance. "These threats may not be currently widespread but have the potential to become so and require urgent public health attention to identify infections and to limit transmission," the report states.
Second most threatening are "serious" infections and include multidrug-resistant Acinetobacter; drug-resistant Campylobacter; fluconazole-resistant Candida; extended spectrum beta-lactamase producing Enterobacteriaceae; vancomycin-resistant Enterococcus; multidrug-resistant Pseudomonas aeruginosa; drug-resistant, nontyphoidal Salmonella; drug-resistant S. typhi; drug-resistant Shigella; methicillin-resistant Staphylococcus aureus; drug-resistant Streptococcus pneumoniae; and drug-resistant tuberculosis.
The CDC considers these "significant" threats that "will worsen and may become urgent without ongoing public health monitoring and prevention activities."
The third level is "concerning," characterized by currently low threat of antibiotic resistance with several antibiotic therapies available. Vancomycin-resistant S. aureus, erythromycin-resistant Streptococcus group A and clindamycin-resistant Streptococcus group B are in this category.
Seven criteria were used in the assessment of threat: the clinical and economic impact of each, the combined numbers of infection, the incidence rate, the 10-year projection of incidence, transmissibility, availability of effective antibiotics, and barriers to prevention. Dr. Frieden outlined what he said the CDC believed were four important measures for turning the tide in the public’s favor, including infection prevention (safe food handling, hand washing, etc.) and using state-of-the-art surveillance to track the occurrence of drug-resistant infections nationally. But antibiotic stewardship, and research and development received the most discussion during the briefing.
Dr. Michael Bell, deputy director of the CDC’s division of health care quality promotion, said that since the advent of penicillin: "We’ve seen every last antibiotic end up having substantial resistance. Just having a new drug is not going to be enough.
"We applaud FDA’s efforts to make new drug development less burdensome and more rapid, but at the same time, we are reassured to know they are proven and safe. We need to make sure we intensely maintain stewardship and that we don’t waste yet another precious drug."
Dr. Frieden pointed to collaboration with the Center for Medicare and Medicaid Services, which he said has begun "incentivizing" hospitals to track infection rates and use good stewardship practices. He also stated that patients who insist their doctors prescribe antibiotics need to understand that getting "more medication" isn’t the solution, but the "right medication" is.
Although drug-resistance–related mortality occurs in the community at large, both Dr. Frieden and Dr. Bell stressed that the first line of action was to curb infection rates in the health care setting and pointed to several recent CDC initiatives, such as the National Healthcare Safety Network, a surveillance database that allows health care facilities and departments of health across the country to share data about outbreaks in their communities, among other information.
When asked about environmental factors contributing to the rising levels of drug-resistance, such as the use of antibiotics in agricultural livestock production, Dr. Bell responded: "We support appropriate antibiotic use across the board. There is always going to be bleed-over in the environment and the ecosystem. Where some of these bacteria are making people sick, there is an overlap with intensive care units, so we do continue to focus a great deal on the health care system. That’s the priority."