Differences in virulence genes frequency among VTEC isolates from cattle, foods and environment

LUCCHESI, PAULA M. A.; KRÜGER, ALEJANDRA; PADOLA, NORA L.; ETCHEVERRÍA, ANALÍA I.; SANZ, MARCELO E.; FERNÁNDEZ, DANIEL; ALONSO, M.P.; POLIFRONI, ROSANA; ARROYO, GUILLERMO H.; PARMA, ALBERTO E.

Amsterdam

Congreso; 8th INTERNATIONAL SYMPOSIUM ON SHIGA TOXIN (VEROCYTOTOXIN)-PRODUCING Escherichia coli; 2012

Comité Internacional

Introduction & Objectives: The aims of this study were to asses the prevalent virulence genes and their combinations among a collection of VTEC isolates obtained from bovine cattle, foods and the environment, and to compare the results among isolates from different origins: calves, grown calves, adult cattle, foods and environment. Material & Methods:The isolates had been obtained from bovine cattle (451 isolates comprising: 95 from calves, 75 from grown calves, and 281 from adult cattle which include dairy cows, feedlot cattle and cattle at slaughter), meat (74 isolates) and the environment of dairy farms (20 isolates). They were characterized by a multiplex PCR that detects vt1,vt2, eae, ehxA and saa. Results:The vt2 gene was present in average in 85.1 % of the isolates, followed by ehxA and saa genes (63.7% and 35.6 %, respectively). When the isolates were grouped according to the origin, some marked differences in gene frequency were detected. The eae gene was detected in a high frequency in isolates from calves and the environment (74.7% and 65%, respectively), whereas the frequency was