title: Screening municipal wastewater effluent and surface water used for drinking water production for the presence of ampicillin and vancomycin resistant enterococci.
abstract: The emergence of clinical enterococcal isolates that are resistant to both ampicillin and vancomycin is a cause of great concern, as therapeutic alternatives for the treatment of infections caused by such organisms are becoming limited. Aquatic environments could play a role in the dissemination of antibiotic resistant enterococci. This study investigated the presence of ampicillin and vancomycin resistant enterococci in the treated effluent of six wastewater treatment plants (WWTPs) and in surface water used as a source for drinking water production in the Netherlands. Membrane filtration in combination with selective media with ampicillin or vancomycin was applied to determine the presence of ampicillin resistant Enterococcus (ARE) and vancomycin resistant Enterococcus (VRE) species. Ampicillin resistant Enterococcus faecium (minimal inhibitory concentration (MIC) >16μg/mL; n=1033) was observed in all studied WWTP effluents. In surface water used for drinking water production (intake locations), no ARE or VRE were observed. At both types of location, intrinsic vancomycin resistant Pediococcus spp., Leuconostoc spp. and Lactobacillus spp. were isolated with the vancomycin medium. The ampicillin resistant E. faecium (AREfm) isolates (n=113) did not contain the vanA or vanB gene, but MIC testing for vancomycin showed intermediate vancomycin resistance (2-8μgmL(-1)) to occur in these AREfm strains. This study documents the discharge of ampicillin resistant E. faecium strains with intermediate vancomycin resistance by the WWTPs into the surface water, but no presence of these strains downstream at intake locations for drinking water production.
authors.affiliation: Het Waterlaboratorium, J.W. Lucasweg 2, 2031 BE Haarlem, The Netherlands; Delft University of Technology, Faculty Civil Engineering & Geosciences, Department of Water Management, Stevinweg 1, 2628 CN Delft, The Netherlands. Electronic address: maja.taucer@hetwaterlaboratorium.nl.
authors.forename: Maja
authors.initials: M
authors.lastname: Taučer-Kapteijn
authors.affiliation: Het Waterlaboratorium, J.W. Lucasweg 2, 2031 BE Haarlem, The Netherlands. Electronic address: wim.hoogenboezem@hetwaterlaboratorium.nl.
authors.forename: Wim
authors.initials: W
authors.lastname: Hoogenboezem
authors.affiliation: Het Waterlaboratorium, J.W. Lucasweg 2, 2031 BE Haarlem, The Netherlands.
authors.forename: Laura
authors.initials: L
authors.lastname: Heiliegers
authors.affiliation: Het Waterlaboratorium, J.W. Lucasweg 2, 2031 BE Haarlem, The Netherlands.
authors.forename: Danny
authors.initials: D
authors.lastname: de Bolster
authors.affiliation: Delft University of Technology, Faculty Civil Engineering & Geosciences, Department of Water Management, Stevinweg 1, 2628 CN Delft, The Netherlands; KWR Watercycle Research Institute, Groningenhaven 7, 3433 PE Nieuwegein, The Netherlands. Electronic address: g.medema@tudelft.nl.
authors.forename: Gertjan
authors.initials: G
authors.lastname: Medema
mesh_terms: D000667:Ampicillin / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D019729:Carbon-Oxygen Ligases / Q000235:genetics; D060766:Drinking Water / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial; D016984:Enterococcus faecium / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D004784:Environmental Monitoring; D005618:Fresh Water / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D014640:Vancomycin / Q000494:pharmacology; D065507:Vancomycin-Resistant Enterococci / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D062065:Wastewater / Q000382:microbiology*; D014873:Water Pollutants / Q000302:isolation & purification
chemical_list: D000667:Ampicillin; D001426:Bacterial Proteins; D019729:Carbon-Oxygen Ligases; D060766:Drinking Water; D014640:Vancomycin; D062065:Wastewater; D014873:Water Pollutants; C071437:VanA ligase, Bacteria; C079913:VanB protein, Enterococcus
keywords: E. faecium; Enterococcus spp.; VRE; Wastewater effluent; vanA; vanB