Genotypes and phenotypes of Shiga toxin producing-Escherichia coli isolated from healthy cattle in Thailand - 24/08/11

Abstract |
Shiga toxin producing-Escherichia coli (STEC) has not yet been identified as an important aetiologic agent of human disease in Thailand. To evaluate the potential for STEC to contribute to human disease in Thailand, 139 fecal samples were collected from healthy cattle from five different provinces and analysed by genotypic and phenotypic methods for STEC. Of 139 samples, 27 (19.4%) were positive for stx1 and/or stx2 by multiplex polymerase chain reaction, or for O157 lipopolysaccharide (LPS) by immunoassay. Isolates positive for stx and/or O157 were subdivided into 49 strains that varied in the presence of the virulence determinants stx1+/stx2+ (22 strains), stx2+ (22 strains), stx1+ (4 strains), and O157 LPS (1 strain). Within these 49 distinguishable strains, other virulence determinants varied as follows: hlyA+ (77.6%), eae+ and tir+ (4.1%), and katP+ (6.12%). The most predominant profile (22 isolates) was stx1+/stx2+, eae−, tir−, etpD−, hlyA+, katP−. For further characterization of the isolated strains by two molecular typing assays, plasmid profiles and ERIC PCR were performed. The results suggest that the genetic and phenotypic profiles of STEC associated with human disease are not prevalent at this time in cattle in Thailand.
Le texte complet de cet article est disponible en PDF.Keywords : Shiga toxin producing-Escherichia coli, Phenotypes, Genotypes, Virulence genes, E. coli O157
Plan
Vol 48 - N° 2
P. 149-160 - février 2004 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.
L’accès au texte intégral de cet article nécessite un abonnement.
Déjà abonné à cette revue ?