WASHINGTON – Antimicrobial resistance of some foodborne pathogens has declined, but no consistent changes in resistance were found among Campylobacter jejuni (C. jejuni) and C. coli sampled from retail chicken sold at retail, according to two new reports from the Food and Drug Administration.

The 2012 Retail Meat Report and the 2013 Retail Meat Interim Report measure antimicrobial resistance in certain bacteria isolated from raw meat and poultry. Samples are collected through the National Antimicrobial Resistance Monitoring System (NARMS). The retail meat unit of the NARMS program collects samples of chicken, ground turkey, ground beef and pork chops sold at retail stores. NARMS tests for non-typhoidal Salmonella, Campylobacter, Escherichia coli and Enterococcus to determine resistance to antibiotics used in human and veterinary medicine. FDA noted that Enterococcus and most E. coli are included in the tests because they are helpful in understanding how antibiotic resistance occurs and spreads, although they are not considered major foodborne pathogens.

A finding of concern for the FDA was the lack of consistent changes in fluoroquinolone resistance among C. jejuni and C. coli recovered from retail chicken. The agency withdrew approval for the use fluoroquinolones in poultry in 2005.

Otherwise, the FDA noted mostly encouraging trends revealed from the agency's findings.

Recent declines in third-generation cephalosporin resistance among poultry meats continued in 2012 and 2013, although current cephalosporin resistance levels remain above 2002 levels.

Antimicrobial resistance in Salmonella found on chicken sold at retail declined to 28 percent in 2012 from a high of 38 percent in 2009. Resistance continued to decline in 2013 to 20 percent.

Drug-resistant pathogens in ground turkey fell to 9 percent in 2013, compared to a peak of 22 percent in 2011 and 18 percent in 2012.

Findings for meat products sold at retail also were positive, according to FDA. Salmonella from retail meats were not resistant to ciprofloxacin, one of the most important antibiotics for treating Salmonella infections, the agency noted. Additionally, Salmonella from retail meats remained susceptible to azithromycin, another important antibiotic recommended for treatment of Salmonella and other intestinal pathogens.

FDA also reported a decline in the overall population of Salmonella isolates that were resistant to three or more classes of antibiotics — also known as multi-drug resistant Salmonella.

In 2012, only 1 percent of C. jejuni from retail chicken were resistant to erythromycin, the leading choice for treating Campylobacter infections, FDA said.

“NCC is pleased to see many positive trends in the data continue, including a decrease in resistance in several foodborne pathogens, and that first-line antibiotics remain effective in treating illnesses,” said Ashley Peterson, Ph.D., National Chicken Council vice president of scientific and regulatory affairs. “Analyzing resistance patterns, as these reports do, is much more meaningful to public health outcomes than examining antibiotic sales data.  These reports provide a strong case that the continued judicious use of antibiotics by poultry and livestock producers is aiding in the reduction of resistance in various foodborne pathogens.”

The 2012 Retail Meat Report summarizes key findings in antimicrobial resistance related to raw chicken, ground turkey, ground beef and pork chops collected at retail stores. The 2013 Retail Meat Interim Report focuses only on Salmonella. It contains data from January to December 2013.

The 2012 and 2013 reports are available on the FDA website.