What's New ? - 2019

What's New ? - 2019

NARMS: Antimicrobial resistance trends in the USA

25 November, 2019

The National Antimicrobial Resistance Monitoring System (NARMS) released its 2016-2017 NARMS Integrated Summary. The National Antimicrobial Resistance Monitoring System (NARMS) is a national public health surveillance system that monitors foodborne bacteria to determine if they are resistant to various antibiotics used in human and veterinary medicine.
Key findings in the new report include:
-Salmonella resistance to third-generation cephalosporins, fluoroquinolones, or azithromycin has increased. The rise in Salmonella resistance to these drugs means that treatment with them may not always work.
-No resistance to carbapenems was observed among Salmonella isolates from humans, retail meats, and animals. This is important as carbapenems are typically reserved to treat suspected multi-drug resistant infectious diarrhea. In the U.S., carbapenems are not used in food animal production, however due to their importance in human health, they are monitored by NARMS.
-Rates of macrolide and fluoroquinolone resistance remain relatively unchanged in Campylobacter jejuni isolated from humans and chickens, and in Campylobacter coli isolated from cattle and swine. While it is positive that these rates of resistance did not increase, the rates of macrolide resistance in Campylobacter isolated from swine and fluoroquinolone resistance in Campylobacter isolated from cattle warrant further monitoring.
-Colistin: Although isolates were not tested for susceptibility to colistin, the genomes of all Salmonella and selected E. coli isolates were examined for the presence of transmissible colistin resistance genes (mcr-1 through mcr-9).  The mcr-1 gene was found in nine Salmonella isolates and one pathogenic E. coli O157 isolate collected from humans during 2016–2017. During 2016–2017 there were no Salmonella E. coli isolates from food animals or retail meats that harbored mcr-1 through mcr-8 resistance genes. However, a newly discovered colistin resistance gene, mcr-9.1, was found in several isolates from humans and all retail meat and food animal sources.