Contact firstname.lastname@example.org for questions regarding NARMS data and reports.
Persons using assistive technology may not be able to fully access information in these reports. For assistance, please call 240-402-5430.
Antimicrobial resistance (AMR) is considered one of the most important global health challenges. Many factors contribute to the emergence of antimicrobial resistant microorganisms, but the use of antimicrobials in medicine and agriculture is considered the most important factor. Considering the serious consequences of AMR to public health and the economy locally and globally, the White House has announced a National Strategy for Combating Antibiotic Resistant Bacteria (CARB) with specific goals and priorities. A prominent feature of the National Strategy is surveillance.
The National Antimicrobial Resistance Monitoring System (NARMS) Integrated Report is the result of a collaborative effort of the Centers for Disease Control and Prevention (CDC), the U.S. Department of Agriculture (USDA) and the Food and Drug Administration (FDA). NARMS gathers surveillance data from human clinical samples, slaughter samples and retail meat samples. This “One Health” approach to integrated surveillance provides information needed to assess the nature and magnitude of resistance in bacteria moving through the food supply and causing illnesses in humans.
The points listed below summarize important observations from the 2012-2013 NARMS Integrated Report. It should be noted that due to sampling and design limitations, the temporal data comparisons for some food commodities and sampling points are more meaningful than for others. Readers are cautioned that some of the findings may be based on small differences or a small number of isolates and are encouraged to reference the full report for more details.
This year’s report shows that the situation in the United States is stable, but shows somewhat more favorable trends over time than unfavorable ones. Overall resistance remains low for most human infections and there have been measurable improvements in resistance levels in other important areas. A summary of the most important trends is presented below.
- Approximately 80% of human Salmonella isolates are not resistant to any of the tested antibiotics. This has remained relatively stable over the past ten years. Resistance for three important drugs (ceftriaxone, azithromycin and ciprofloxacin) in human non-typhoidal Salmonella isolates remained below 3%.
- Over the past ten years, multidrug resistance (MDR) has remained unchanged in human Salmonella isolates (~10%) and in cattle and chicken isolates collected the USDA Pathogen Reduction/Hazard Analysis and Critical Control Point program (PR/HACCP; ~20%). There was a decline in the proportion of retail chicken Salmonella that were multi-drug resistant compared to the 2008-2012 average.
- Overall, ciprofloxacin resistance has been consistently low among Salmonella isolated from all sources. Similarly, ciprofloxacin resistance in E. coli was absent or very low (0-1.7%) in isolates from retail meats, PR/HACCP chicken and cecal samples.
- Ceftriaxone resistance has declined since 2009 in human (3.4% to 2.5%) and retail chicken (38% to 20%) Salmonella isolates with a parallel drop in resistance among E. coli isolates from retail chicken (12.4% to 4.4%). In 2013, ceftriaxone resistance in human Salmonella Heidelberg isolates was 15%,, down from a peak of 24% in 2010. Ceftriaxone resistance in retail chicken Salmonella Heidelberg remained at 0% since 2011, down from a peak of 32% in 2009.
- Resistance to an important drug pattern (ACSSuT) continued to decline in human isolates of Salmonella Typhimurium.
- Campylobacter jejuni and Campylobacter coli cause about 90% and 10% of human campylobacter infections, respectively. In retail chicken samples, C. jejuni resistance to ciprofloxacin was at its lowest level to date (11%), while ciprofloxacin resistance in C. jejuni isolated from chicken slaughter samples has not declined (22% in 2013). The prevalence of Campylobacter in retail chicken samples has gradually declined over the past 9 years.
- Erythromycin resistance in C. jejuni isolates from both human and chicken sources has remained low (< 3%), and gentamicin resistance in C. coli isolates has steeply declined for both human and food sources after spiking in recent years.
- With the exception of five isolates in the past ten years, no resistance has been detected in Enterococcus to three important drugs: daptomycin, linezolid and vancomycin.
While a majority of the observations in the 2012-2013 NARMS Integrated Report show desirable trends, there are a few findings of potential concern.
- Non susceptibility to ciprofloxacin has increased since in human non-typhoidal Salmonella since 1996.
- There has been no change in ciprofloxacin resistance among human C. jejuni isolates, which remained at 22%; however, ciprofloxacin resistance in human C. coli isolates has increased from 25% in 2005 to 35% in 2013. In contrast to the observed decline in ciprofloxacin resistance in C. jejuni from retail chicken (see above), it did not decline in C. jejuni isolated from chicken carcasses at processing (PR/HACCP).
- Macrolide resistance in human Campylobacter coli doubled from 9% in 2012 to 18% in 2013 and rose comparably in C. coli isolates from PR/HACCP chicken, from a low level of 3.4% in 2011 to 11% in 2013.
- MDR in human isolates of a common Salmonella serotype (l 4,,12:i:-) more than doubled from 18% in 2011 to 46% in 2013. MDR and ceftriaxone resistance in Salmonella serotype Dublin isolated from cattle and human sources has increased. While the incidence of human Salmonella Dublin infections is relatively low, it can cause invasive disease with more severe outcomes, and ranks among the top 4 serotypes isolated from retail ground beef and PR/HACCP samples. MDR Salmonella from turkey products also has increased over the past decade.
- The examples of extremely drug resistant Salmonella and E. coli, while rare, warrant careful attention.