Prevalence of high-priority antibiotic resistant bacteria in the US food supply

Antibiotic use in food animal production negatively impacts human health through the selection of antibiotic resistant foodborne pathogens such as Salmonella and Campylobacter. Antibiotic resistant strains of Escherichia coli and Enterococcus spp. are also common contaminants of US retail meat and poultry, and may negatively impact human health as well. To more fully evaluate consumer risk, the entire range of antibiotic resistant bacteria that contaminate the US food supply must be assessed. However, the National Antibiotic Resistance Monitoring System (NARMS) currently only surveys retail meats for Salmonella, Campylobacter, E. coli and Enterococcus. In the current study, we surveyed retail pork chops, ground beef, ground turkey, and chicken breasts from Arizona, California, District of Columbia, and Illinois for antibiotic resistant strains of Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa. All four bacterial species were identified among the food samples and resistant phenotypes were common. Further studies will have to be conducted to assess the host specificities of these organisms and specifically their ability to colonize or infect humans and to share resistance determinants with human-adapted pathogens.