Carbapenemase producing bacteria in the food supply escaping detection

PLoS One. 2015 May 12;10(5):e0126717. doi: 10.1371/journal.pone.0126717. eCollection 2015.

Abstract

Carbapenem antimicrobials are critically important to human health and they are often the only remaining effective antibiotics for treating serious infections. Resistance to these drugs mediated by acquired carbapenemase enzymes is increasingly encountered in gram-negative bacteria and is considered a public health emergency. Animal origin food products are recognized as a potential source of resistant organisms, although carbapenem resistance has only recently been reported. In western countries there are active resistance surveillance programs targeting food animals and retail meat products. These programs primarily target beef, pork and poultry and focus exclusively on E. coli, Salmonella, Campylobacter spp. and Enterococcus spp. This global surveillance strategy does not capture the diversity of foods available nor does it address the presence of resistance gene-bearing mobile genetic elements in non-pathogenic bacterial taxa. To address this gap, a total of 121 seafood products originating in Asia purchased from retail groceries in Canada were tested. Samples were processed using a taxa-independent method for the selective isolation of carbapenem resistant organisms. Isolates were characterized by phenotypic antimicrobial susceptibility testing, PCR and DNA sequencing. Carbapenemase producing bacteria, all blaOXA-48, were isolated from 4 (3.3%) of the samples tested. Positive samples originated from China (n=2) and Korea (n=2) and included squid, sea squirt, clams and seafood medley. Carbapenemase producing organisms found include Pseudomonas, Stenotrophomonas and Myroides species. These findings suggest that non-pathogenic bacteria, excluded from resistance surveillance programs, in niche market meats may serve as a reservoir of carbapenemase genes in the food supply.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Proteins / genetics
  • Bacterial Proteins / isolation & purification*
  • Canada
  • Carbapenems / therapeutic use
  • China
  • Drug Resistance, Bacterial / genetics
  • Food Microbiology*
  • Humans
  • Pseudomonas / enzymology
  • Pseudomonas / isolation & purification*
  • Pseudomonas / pathogenicity
  • Republic of Korea
  • Seafood / microbiology
  • Stenotrophomonas / enzymology
  • Stenotrophomonas / isolation & purification*
  • Stenotrophomonas / pathogenicity
  • beta-Lactamases / genetics
  • beta-Lactamases / isolation & purification*

Substances

  • Bacterial Proteins
  • Carbapenems
  • beta-Lactamases
  • carbapenemase

Grants and funding

This work was supported by a new investigator start up operating fund from the University of Saskatchewan. Stipend support for B.M. was provided by the Interprovincial Summer Student Research Program at the Western College of Veterinary Medicine. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.