Assessment of a new technique combining a viability test, whole-cell hybridization and laser-scanning cytometry for the direct counting of viable Enterobacteriaceae cells in drinking water.
A new direct approach, called direct viable count (DVC)-FISH-ScanRDI, combining viability measurement, specific detection and sensitive enumeration of highly diluted Enterobacteriaceae cells, was assessed during the summer in water samples from a North American drinking water treatment plant and its distribution system. Major results of this field investigation show a higher sensitivity of the DVC-FISH-ScanRDI approach in enumerating viable Enterobacteriaceae cells in distributed drinking water, relative to a culture-based method, and the increased concentration of viable but non-culturable (VBNC) Enterobacteriaceae cells in distributed water for temperatures above 18 degrees C.
Baudart
Julia
J
NSERC Industrial Chair on Drinking Water, Civil, Geological and Mining Engineering, Ecole Polytechnique de Montréal, Montréal, Qué., Canada H3C 3A7. baudart@obs-banyuls
Olaizola
Amandine
A
Coallier
Josée
J
Gauthier
Vincent
V
Laurent
Patrick
P
D001431:Bacteriological Techniques; D015169:Colony Count, Microbial; D004326:Drinking; D004755:Enterobacteriaceae / Q000166:cytology / Q000254:growth & development* / Q000302:isolation & purification*; D005618:Fresh Water / Q000382:microbiology*; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D047569:Laser Scanning Cytometry / Q000379:methods*; D018508:Water Purification / Q000379:methods