title: Comparative analysis of classical and molecular microbiology methods for the detection of Escherichia coli and Enterococcus spp. in well water.
abstract: The microbiological quality of 165 1 litre well water samples collected in the Québec City region was assessed by culture-based methods (mFC agar, Chromocult coliform agar, Colilert(®), MI agar, Chromocult enterococci, Enterolert™, and mEI agar) and by a molecular microbiology strategy, dubbed CRENAME-rtPCR, developed for the detection of Escherichia coli, Enterococcus spp., Enterococcus faecalis/faecium, and Bacillus atrophaeus subsp. globigii. In these drinking water samples, approved culture-based methods detected E. coli at rates varying from 1.8 to 3.6% and Enterococcus spp. at rates varying from 3.0 to 11.5%, while the molecular microbiology approach for E. coli was found to be as efficient, detecting contamination in 3.0% of samples. In contrast, CRENAME-rtPCR detected Enterococcus spp. in 27.9% of samples while the E. faecalis/faecium molecular assay did not uncover a single contaminated sample, thereby revealing a discrepancy in the coverage of waterborne enterococcal species detected by classical and molecular microbiology methods. The validation of the CRENAME-E. coli rtPCR test as a new tool to assess the quality of drinking water will require larger scale studies elaborated to demonstrate its equivalence to approved methods.
authors.affiliation: Centre de recherche en infectiologie de l'Université Laval, Centre de recherche du CHUQ, 2705 Laurier Blvd., Québec City, Québec, Canada G1V 4G2.
authors.forename: Andrée F
authors.initials: AF
authors.lastname: Maheux
authors.forename: Vicky
authors.initials: V
authors.lastname: Huppé
authors.forename: Luc
authors.initials: L
authors.lastname: Bissonnette
authors.forename: Maurice
authors.initials: M
authors.lastname: Boissinot
authors.forename: Lynda
authors.initials: L
authors.lastname: Rodrigue
authors.forename: Ève
authors.initials: È
authors.lastname: Bérubé
authors.forename: Michel G
authors.initials: MG
authors.lastname: Bergeron
mesh_terms: D015373:Bacterial Typing Techniques / Q000379:methods*; D016983:Enterococcus / Q000145:classification* / Q000235:genetics / Q000254:growth & development; D004926:Escherichia coli / Q000145:classification* / Q000235:genetics / Q000254:growth & development; D011792:Quebec; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014871:Water Microbiology; D060986:Water Wells / Q000382:microbiology*