A comparison of extended spectrum β-lactamase producing Escherichia coli from clinical, recreational water and wastewater samples associated in time and location

PLoS One. 2017 Oct 17;12(10):e0186576. doi: 10.1371/journal.pone.0186576. eCollection 2017.

Abstract

Extended spectrum β-lactamase producing Escherichia coli (ESBL-EC) are excreted via effluents and sewage into the environment where they can re-contaminate humans and animals. The aim of this observational study was to detect and quantify ESBL-EC in recreational water and wastewater, and perform a genetic and phenotypic comparative analysis of the environmental strains with geographically associated human urinary ESBL-EC. Recreational fresh- and saltwater samples from four different beaches and wastewater samples from a nearby sewage plant were filtered and cultured on differential and ESBL-selective media. After antimicrobial susceptibility testing and multi-locus variable number of tandem repeats assay (MLVA), selected ESBL-EC strains from recreational water were characterized by whole genome sequencing (WGS) and compared to wastewater and human urine isolates from people living in the same area. We detected ESBL-EC in recreational water samples on 8/20 occasions (40%), representing all sites. The ratio of ESBL-EC to total number of E. coli colony forming units varied from 0 to 3.8%. ESBL-EC were present in all wastewater samples in ratios of 0.56-0.75%. ST131 was most prevalent in urine and wastewater samples, while ST10 dominated in water samples. Eight STs and identical ESBL-EC MLVA-types were detected in all compartments. Clinical ESBL-EC isolates were more likely to be multidrug-resistant (p<0.001). This study confirms that ESBL-EC, including those that are capable of causing human infection, are present in recreational waters where there is a potential for human exposure and subsequent gut colonisation and infection in bathers. Multidrug-resistant E. coli strains are present in urban aquatic environments even in countries where antibiotic consumption in both humans and animals is highly restricted.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Bathing Beaches
  • Drug Resistance, Multiple, Bacterial
  • Epidemiological Monitoring
  • Escherichia coli / drug effects
  • Escherichia coli / genetics
  • Escherichia coli / growth & development
  • Escherichia coli / isolation & purification*
  • Escherichia coli Infections / epidemiology
  • Escherichia coli Infections / microbiology
  • Fresh Water / microbiology*
  • Gene Expression
  • Genome, Bacterial*
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Microbial Sensitivity Tests
  • Multilocus Sequence Typing
  • Norway / epidemiology
  • Recreation
  • Urinary Tract Infections / epidemiology
  • Urinary Tract Infections / microbiology
  • Wastewater / microbiology*
  • Water Microbiology*
  • beta-Lactamases / genetics*

Substances

  • Anti-Bacterial Agents
  • Waste Water
  • beta-Lactamases