USA: NARMS reports antimicrobial resistance patterns in swine

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. The 2016-2017 report summary shows changes in antimicrobial resistance in hogs and pork.

E. coli

• During 2015–2017, ceftriaxone-resistant E. coli continued to decline or remained below 5% in all animal sources except retail pork chops and market swine cecal samples, where it increased to 4.4% (from 1.2%) and 6.3% (from 2.7%), respectively.
• During 2015–2017, azithromycin resistance was not detected in E. coli from retail meat samples. Among cecal samples from all animal sources, E. coli isolates with azithromycin resistance has remained below 3%.
• Among cecal samples from all food animals, MDR E. coli either decreased or remained stable, except in market swine (which showed an increase from 24% in 2015 to 27% in 2017) and sows (which showed an increase from 13% in 2015 to 16% in 2017).

Enterococcus

• Between 2013 and 2017 there was an increase in chloramphenicol resistance among E. faecalis from market swine ceca (from 15% to 23%) and retail pork (from 2.1% to 5.5%). Chloramphenicol resistance in sow ceca declined from 21% to 8.5% during the same time period.
• During 2015–2017, MDR E. faecalis decreased or remained stable among cecal samples from all commodities except market swine and sows, where MDR increased from 55% to 60%.

For the full summary, click here.