Isolation of Yersinia enterocolitica from surface and well waters in Ontario

Abstract

Y. enterocolitica was isolated from 43 surface- and well-water samples and 1 municipal supply. In many cases these samples were negative for coliform bacteria. After incubation of membrane filters on M-Endo agar LES at 35.degree. C for total coliform analysis, filters were held an additional 24 h at room temperature. This method was more productive for isolation of waterborne types of Y. enterocolitica than was cold enrichment in buffer alone or in combination with modified Rappaport broth. Most of the water isolates were atypical in being rhamnose-positive. Eighteen isolates (38%) were serotypable, presenting 9 different serotypes with 0:4 occurring most frequently followed by 0:6,30. Water isolates of serotype 0:6,30 resemble human strains of the same serotype.