Detection of vancomycin-resistant Enterococcus faecium hospital-adapted lineages in municipal wastewater treatment plants indicates widespread distribution and release into the environment

Research output: Contribution to journalArticlepeer-review


  • Theodore Gouliouris
  • Kathy E Raven
  • Catherine Ludden
  • Francesc Coll
  • Beth Blane
  • Plamena Naydenova
  • Carolyne Horner
  • Nicholas M Brown
  • Jukka Corander
  • Direk Limmathurotsakul
  • Julian Parkhill
  • Sharon J Peacock

Colleges, School and Institutes

External organisations

  • University of Cambridge
  • London School of Hygiene and Tropical Medicine
  • Addenbrooke's Hospital
  • Mahidol University
  • University of Oslo
  • British Society for Antimicrobial Chemotherapy


Vancomycin-resistant Enterococcus faecium (VREfm) is a leading cause of healthcare-associated infection. Reservoirs of VREfm are largely assumed to be nosocomial although there is a paucity of data on alternative sources. Here, we describe an integrated epidemiological and genomic analysis of E. faecium associated with bloodstream infection and isolated from wastewater. Treated and untreated wastewater from 20 municipal treatment plants in the East of England, United Kingdom was obtained and cultured to isolate E. faecium, ampicillin-resistant E. faecium (AREfm), and VREfm. VREfm was isolated from all 20 treatment plants and was released into the environment by 17/20 plants, the exceptions using terminal ultraviolet light disinfection. Median log10 counts of AREfm and VREfm in untreated wastewater from 10 plants in direct receipt of hospital sewage were significantly higher than 10 plants that were not. We sequenced and compared the genomes of 423 isolates from wastewater with 187 isolates associated with bloodstream infection at five hospitals in the East of England. Among 481 E. faecium isolates belonging to the hospital-adapted clade, we observed genetic intermixing between wastewater and bloodstream infection, with highly related isolates shared between a major teaching hospital in the East of England and 9/20 plants. We detected 28 antibiotic resistance genes in the hospital-adapted clade, of which 23 were represented in bloodstream, hospital sewage, and municipal wastewater isolates. We conclude that our findings are consistent with widespread distribution of hospital-adapted VREfm beyond acute healthcare settings with extensive release of VREfm into the environment in the East of England.

Bibliographic note

© 2019 Gouliouris et al.; Published by Cold Spring Harbor Laboratory Press.


Original languageEnglish
Pages (from-to)626-634
Number of pages9
JournalGenome Research
Issue number4
Publication statusPublished - 1 Apr 2019


  • Anti-Bacterial Agents/toxicity, Cross Infection/microbiology, Drug Resistance, Bacterial, England, Enterococcus faecium/drug effects, Genome, Bacterial, Vancomycin/toxicity, Waste Water/microbiology