Epidemiology of ESBL-producing Escherichia coli from repeated prevalence studies over 11 years in a long-term-care facility

Antimicrob Resist Infect Control. 2021 Oct 19;10(1):148. doi: 10.1186/s13756-021-01013-7.

Abstract

Background: Escherichia coli sequence type (ST) 131 H30 is an emerging multidrug resistant subclone, known to spread and cause outbreaks in long-term care facilities (LTCFs).

Objectives and methods: From 2010 through 2020, we performed 11 yearly surveillance studies for determining the prevalence of digestive carriage of ESBL-producing E. coli (ESBL-EC) among residents in a university-affiliated LCTF. Sequencing and genotyping of selected isolates were performed to characterize temporal trends in the prevalence and epidemic potential of ESBL-EC subclones, and for evaluating a potential rebound effect following discontinuation of contact precautions for ESBL-EC carriers in January 2019.

Results: This study included 2'403 LTCF residents, with 252 (10.5%) positive for ESBL-EC. Among the 236 ESBL-EC isolates available for typing, 58.0% belonged to the ST131 lineage, including 94/137 (68.6%) ST131 H30 isolates. An increasing yearly prevalence was observed for ESBL-EC (from 4.6 to 9.4%; p = 0.11), but not for the ST131 H30 subclone, which peaked in 2015 and declined thereafter. Multiple previously unnoticed ESBL-EC outbreaks occurred in the LTCF. Since 2018, we noted the clonal expansion of a rare ST131 H89 subclone (O16:H5) harboring CTX-M-14 and CTX-M-24. No rebound effect was observed in ESBL-EC prevalence nor in the different subclones following discontinuation of contact precautions for ESBL-EC carriers since 2019.

Conclusion: Clonal fluctuation was observed for ST131 H30 ESBL-EC with a current decline in prevalence. Surveillance should include the evolution of ST131 non-H30 subclones, which may spread in LTCFs. Our findings suggest that discontinuation of contact precautions for ESBL-EC carriers in LTCFs may be safely implemented, in support of European recommendations to limit ESBL-producing Enterobacteriaceae control measures in endemic settings to non-E. coli.

Keywords: Antimicrobial resistance; Escherichia coli; Fluoroquinolone resistance; Intestinal colonization; Long-term care facility; Molecular epidemiology; PCR; ST131; Surveillance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carrier State / epidemiology*
  • Carrier State / microbiology*
  • Cross-Sectional Studies
  • Disease Reservoirs / microbiology
  • Drug Resistance, Multiple
  • Escherichia coli / classification
  • Escherichia coli / enzymology*
  • Escherichia coli / genetics
  • Escherichia coli Infections / epidemiology*
  • Escherichia coli Infections / microbiology*
  • Escherichia coli Infections / prevention & control
  • Feces / microbiology
  • Humans
  • Long-Term Care
  • Prevalence
  • Rectum / microbiology
  • Universal Precautions
  • beta-Lactamases / metabolism*

Substances

  • beta-Lactamases