The u.s. Food and Drug Administration (FDA) has released an executive report summarizing the data collected by the National Antimicrobial Resistance Monitoring system (NARMs) since 1996. Implemented by FDA, the Centers for Disease Control and Prevention, and the u.s. Department of Agriculture, NARMs tracks antibiotic resistance in foodborne bacteria, focusing on antibiotics “that are considered important to human health as well as multidrug resistance [MDR]” to three or more antibiotic classes.

According to an August 11, 2014, news release, FDA identified “positive and negative trends in antimicrobial resistance in bacteria isolated from humans, retail meats and food animals.” For non-typhoidal Salmonella, which showed no resistance in 85 percent of samples isolated from humans, the report found that “MDR among humans, slaughtered chicken and slaughtered swine was the lowest [in 2011] since testing began,” though “MDR Salmonella from retail poultry meats generally increased.” NARMs also concluded that “erythro- mycin resistance in Campylobacter jejuni remained at less than 4% in isolates obtained from humans, retail chicken and slaughtered chicken,” while “ceftri- axone resistance among E. coli isolates from retail chicken increased from 8% in 2002 to 13% in 2011,” with ground turkey isolates showing a 9 percent increase in ceftriaxone resistance during the same period.

In addition, FDA noted how restrictions on the use of certain antibiotic classes have affected drug resistance levels in poultry, cattle and retail meats. “Resistance to third-generation cephalosporins, another important drug  class for the treatment of Salmonella infections, rose among isolates from retail ground turkey between 2008 and 2011 and among certain Salmonella serotypes in cattle between 2009 and 2011,” states the report. “In April 2012, FDA prohibited certain uses of cephalosporin drugs in cattle, swine, chickens, and turkeys. NARMs will continue to monitor these trends over time.”