Escherichia coli O157:H7 prevalence and virulence gene detection in raw meat in Bahir Dar City, Ethiopia

Escherichia coli O157:H7 serotype is worldwide zoonotic pathogen responsible for the majority of severe cases of human enterohemorrhagic Escherichia coli disease. A cross sectional study was designed from November 2019-March 2020 with the aim of isolating E. coli O157:H7, detecting virulence genes and assessing its antimicrobial resistance pattern from raw meat ready to eat ( kurt ) from butcher shop at Bahir Dar city. A total of 74 beef samples were collected and processed using standard microbiological procedures to isolate and identify the bacterium and determine their antimicrobial susceptibility patterns. Genomic DNA of the isolates was examined with conventional polymerase chain reactions to detect virulence genes. Accordingly 21 E. coli O157:H7 were isolated. The PCR virulence gene detection showed that 61.9% and 38.1% of the isolated harbours stx ₁ and eaeA genes respectively. Isolates were further subjected to the in vitro antimicrobial sensitivity test and showed the degree of susceptibility ranges from 62% − 100% and resistance rate were between 4.8% and 33.3%. Only 6 (28.6%) of them showed the presence of resistance for two drugs amoxicillin and chloramphenicol. The higher incidence of the stx ₁ and eaeA gene in meat samples indicates the risk alert of E. coli O157 infection. Therefore, appropriate measures are now needed to wards food safety, knowledge gap of butcher shop workers and building standardized abattoir in the area to prevent the spread of this life-threatening food borne disease in our city and our country Ethiopia having the habit eating raw beef.