Clinical question: What antibiotic-resistant bacteria are the greatest threats for the next 10 years?
Background: Two million people suffer antibiotic-resistant infections yearly, and 23,000 die each year as a result. Most of these infections occur in the community, but deaths usually occur in healthcare settings. Cost estimates vary but may be as high as $20 billion in excess direct healthcare costs.
Study design: The CDC used several different surveys and databanks, including the National Antimicrobial Resistance Monitoring System, to collect data. The threat level for antibiotic-resistant bacteria was determined using several factors: clinical impact, economic impact, incidence, 10-year projection of incidence, transmissibility, availability of effective antibiotics, and barriers to prevention.
Setting: United States.
Synopsis: The CDC has three classifications of antibiotic-resistant bacteria: urgent, serious, and concerning. Urgent threats are high-consequence, antibiotic-resistant threats because of significant risks identified across several criteria. These threats might not currently be widespread but have the potential to become so and require urgent public health attention to identify infections and to limit transmission. They include carbapenem-resistant Enterobacteriaceae, drug-resistant Neisseria gonorrhoeae, and Clostridium difficile (does not have true resistance, but is a consequence of antibiotic overuse).
Serious threats are significant antibiotic-resistant threats. These threats will worsen and might become urgent without ongoing public health monitoring and prevention activities. They include multidrug-resistant Acinetobacter, drug-resistant Campylobacter, fluconazole-resistant Candida (a fungus), extended-spectrum β-lactamase-producing Enterobacteriaceae, vancomycin-resistant Enterococcus, multidrug-resistant Pseudomonas aeruginosa, drug-resistant non-typhoidal Salmonella, drug-resistant Salmonella Typhimurium, drug-resistant Shigella, methicillin-resistant Staphylococcus aureus, drug-resistant Streptococcus pneumonia, and drug-resistant tuberculosis.
Concerning threats are bacteria for which the threat of antibiotic resistance is low, and/ or there are multiple therapeutic options for resistant infections. These bacterial pathogens cause severe illness. Threats in this category require monitoring and, in some cases, rapid incident or outbreak response. These include vancomycin-resistant Staphylococcus aureus, erythromycin-resistant Group A Streptococcus, and clindamycin-resistant Group B Streptococcus. Research has shown patients with resistant infections have significantly longer hospital stays, delayed recuperation, long-term disability, and higher mortality. As resistance to current antibiotics occurs, providers are forced to use antibiotics that are more toxic, more expensive, and less effective.
The CDC recommends four core actions to fight antibiotic resistance:
- Preventing infections from occurring and preventing resistant bacteria from spreading (immunization, infection control, screening, treatment, and education);
- Tracking resistant bacteria;
- Improving the use of antibiotics (antibiotic stewardship); and
- Promoting the development of new antibiotics and new diagnostic tests for resistant bacteria.
Bottom line: Antibiotics are a limited resource. The more antibiotics are used today, the less likely they will continue to be effective in the future. The CDC lists 18 antibiotic-resistant organisms as urgent, serious, or concerning and recommends actions to combat the spread of current organisms and emergence of new antibiotic organisms.
Citation: Centers for Disease Control and Prevention. Antibiotic resistance threats in the United States, 2013. CDC website. September 16, 2013. Available at: www.cdc.gov/drugresistance/threat-report-2013. Accessed Nov. 30, 2013.