Characterization of fecal extended-spectrum-β-lactamase-producing Escherichia coli in a remote community during a long time period

Antimicrob Agents Chemother. 2013 Oct;57(10):5060-6. doi: 10.1128/AAC.00848-13. Epub 2013 Aug 5.

Abstract

Carriage of extended-spectrum beta-lactamase-producing enterobacteria (ESBL-E) has increased in community settings. Little is known about their long-term evolution. French Guiana Amerindians living in a very remote village, already sampled in 2001 and 2006 for ESBL-E fecal carriage, were screened again in October 2010. Sociodemographic data and antibiotic intake data were collected during the previous year. ESBL-E strains collected in 2010 and their plasmid contents were typed. The results were compared to those of the previous campaigns. The prevalence of ESBL-E carriage in 2010 was 5.3%, whereas it was 8.0% and 3.2% in 2006 and 2001, respectively. As previously determined, no individual factor was associated with carriage, including personal antibiotic exposure. However, overall antibiotic use had decreased to a 0.67 treatments/subject/year in 2010 versus 1.09 in 2006 (P < 0.001), which supports the idea that population exposure to antibiotics impacts on ESBL-E community carriage rates. A wide diversity of ESBL Escherichia coli strains belonging to the A0, A1, B1, and D2 phylogroups and producing the CTX-M-1, CTX-M-2, and CTX-M-8 enzymes were isolated. Despite the overall genetic diversity of the strains evaluated by repetitive extragenic palindromic PCR (rep-PCR) and multilocus sequence typing, two CTX-M-1-producing clones were found to have spread. In contrast, similar ESBL-bearing I1/Iγ plasmids were present in various strains both within and between carriers, suggesting high rates of plasmid transfer. Our results suggest that overall antibiotic exposure affects ESBL-E fecal carriage in the community. ESBL-E spread may be the result of both strain dissemination and the transfer of plasmids in intestinal microbiota.

MeSH terms

  • Adolescent
  • Adult
  • Anti-Bacterial Agents / pharmacology*
  • Escherichia coli / classification
  • Escherichia coli / drug effects*
  • Escherichia coli / enzymology*
  • Escherichia coli Proteins / metabolism
  • Feces / microbiology*
  • Female
  • Humans
  • Male
  • Phylogeny
  • Risk Factors
  • Young Adult
  • beta-Lactamases / metabolism

Substances

  • Anti-Bacterial Agents
  • Escherichia coli Proteins
  • CTX-M-9 protein, E coli
  • beta-lactamase CTX-2
  • beta-lactamase TEM-3
  • beta-Lactamases