RESUMO
Background and aim: Escherichia coli O[157]:H[7] is now recognized as an important cause of diarrhea, hemorrhagia colitis and hemolytic-uremic syndrome worldwide. Meat contaminated with animal feces is probably the major source of the E. coli O[157]:H[7]. In this study, we investigated the prevalence of E. coli O[157]:H[7] in meat samples of sheep in Isfahan from August 2008 to January 2010
Methods: A total of 148 sheep carcasses in Isfahan slaughterhouse were assessed for E. coli O[157]:H[7] using the standard cultural and polymerase chain reaction [PCR] methods. Bacteriological examinations were performed by using Triptone Soya Broth containing Novobiocin [TSB-n] as an enrichment media and then sorbitol MacConkey agar plates supplemented with Cefixime and Tellurite [CT-SMAC] a selective plating media. Suspected colonies of E. coli O[157]:H[7], identified by bacteriological methods, were tested by PCR
Results: Using cultural method, 43 [29.1%] and 10 [6.8%] samples were positive for E. coli and E. coli O[157]:H[7], respectively. Only 5 sorobitol negative E. coli strains were identified as E. coli O[157]:H[7], using polymerase chain reaction. The seasonal prevalence of E. coli O[157]:H[7] in samples were 0-9.7% and it was at its highest level in Spring and Summer
Conclusion: These results indicate that sheep can be a reservoir for E. coli O[157]:H[7] and sheep meat may serve as a vehicle for the pathogen transmission to human