MOLECULAR DETECTION OF ENTEROHAEMORRHAGIC ESCHERICHIA COLI IN RAW BEEF MEAT FROM ABEOKUTA, OGUN STATE, NIGERIA

Abstract

The presence of Enterohaemorrhagic Escherichia coli in beef and beef products is of public health importance. Therefore, the current study was carried out to evaluate the prevalence of E. coli serotype O157:H7 from raw beef collected from  Abeokuta. Meat samples from selected abattoir and open beef omarket in Abeokuta were aseptically collected into sterile peptone water, incubate at 37C for 24 hours and subcultured on MacConkey agar. The bacteria isolated were identified using standard method and owere cultured on Sorbitol MacConkey agar, incubated at 37C for 24hrs. Serological test was performed using O157:H7 polyvalent and monovalent anti-E. coli O and H sera. The presence of Shiga toxin 1 and 2 was detected by Polymerase Chain Reaction method. Antibiotic susceptibility testing was carried out using disk diffusion technique. Out of the 100 samples collected 60% yielded lactose fermenting colonies identified biochemically as E. coli, 43.3% from the abattoirs and 56.7% were from the open market. Only 3.3% of the Escherichia coli were non-Sorbitol fermenter and were confirmed as Enterohaemorrhagic Escherichia coli O157:H7 serologically, 1.7% carries the Stx 1 gene. The E. coli were resistant to Augmentin 95% and Cefuroxime 83.3%, Gentamycin 20%, Ofloxacin 21.7%, Ciprofloxacin 26.7%, Cefixime 38.3% and Ceftazidime 43.3%. The isolates that possessed Stx 1 gene were resistant to all the antibiotics tested. The meat samples in the abattoir and open market were contaminated with E coli which contain enterohaemorrhagic strains producing shiga toxin 1 (Stx 1) and were highly resistant to antibiotics.