Investigation of Escherichia coli contamination and virulence genes in meat foods from Wuhou district of Chengdu city

The contamination of Escherichia coli in meat foods of Chengdu city and virulent characteristics of isolated strains were investigated in this study,which could lay basis for preventing and controlling of E. coli contamination in food and guaranteeing food safety. Meat samples were collected from the supermarkets and retail markets located in Wuhou district of Chengdu city from 2011 to 2013. These samples were enriched and E. coli strains were isolated and identified. DNA of all the isolated strains were extracted and subjected to PCR detection for eight virulence genes(eae A,stx1 A,stx2A,hly A,agg R,est,elt A and bfp A). The detection rate of E. coli for raw meat samples was 81.07%,and the detection rate of E. coli for cooked meat samples was 40%.49 strains were detected to having more than one virulence genes from 324 isolated E. coli strains. The main prevalent virulence genes were eae A and agg R,while est and bfp A genes could not be detected. The contamination of E. coli in meat samples was found to be very high. These results would provide significant data for the control and survey of foodborne E. coli in meat samples.