Abstract of research

Detection of virulence genes of enterohaemorrhagic E. Coli isolated from some meat products by polymerase chain reaction.

1 Department of Bacteriology, Immunology and Mycology, Faculty of Veterinary Medicine, Benha University. 2Animal Health Research “Shebin El- Kom branch”.

Abstract

A grand total of 105 meat product samples of minced meat, sausage and luncheon (35 of each) were duplicated bacteriologically examined to detect Enterohaemorrhagic E.coli prevalence and some virulence genes. One replicate was processed for EHEC non O157 by using conventional method for isolation and identification of E.coli and the other for E.coli O157:H7, then serological typing and PCR technique for specific stx1, stx2, cvcC and hlyA genes from 6 random samples were applied. E.coli was isolated from 12 samples (34%), 9 samples (25.7%) and 11 samples (31%) of the examined minced meat, sausage and luncheon, respectively. The isolated serotypes of EHEC were O26 (5 strains) 15.6%, O111 (3 strains) 9.4% and O157 (3 strains) 17.6%. The incidence of EHEC O26 were (2 strains) 5.7%, (2 strains) 5.7%, (1strain) 2.85%, incidence of O157:H7 were (2 strain) 5.7%, (1 strain) 2.85%, 0% in minced meat, sausage and luncheon, respectively. The incidence of O111 was 2.85% from each the type meat products. PCR results indicated that stx2 and cvaC virulence genes were detected in the same studied strain (O157:H7 from minced meat sample), while stx1 and hIyA genes were not detected. Accordingly, meat products may constitute an important reservoir for EHEC and PCR technique is the most sensitive and efficient approach for detection of EHEC genes.