Genotypic and Phenotypic Assessment of Antibiotic Resistance and Recognition of Virulence Factors in Escherichia coli O157 Serogroup Isolated from Hamburger

ESCHERICHIA coli (E. coli) O157 isan important food-borne pathogen. The existing survey was addressed to assess the incidence, phenotypic and genotypic resistance profile toward antibiotics and incidence of virulence factors amongst the E. coli O157 isolates recovered from hamburger. Two-hundred hamburger samples were collected from superstores of Mazandaran, Iran. Hamburger samples were cultured and phenotypic antibiotic resistance pattern was deliberated using disk diffusion test. Isolated E. coli O157 bacteria were identified by PCR. Nineteen out of 200 (9.50%) hamburger samples were contaminated with E. coli O157. Brand C (18%) had the uppermost contamination rate, while brand D (4%) had the lower most. E. coli O157 isolates displayed the uppermostincidence of resistance towardtetracyc lines (100%), ampicillin (100%) and gentamicin (89.47%). All of isolates were resistant toward an antibiotic, while incidence of resistance towardover 6 antibiotics was 36.84%. CITM (89.47%), CTX (89.47%), aac(3)-IV (78.94%), dfrA1 (63.15%), sul1 (63.15%) and tetA (57.89%) were the most generallyidenti fied antibiotic resistance genes. Incidence of ehlyA, stx2, stx1 and eae A were 100%, 42.10%, 100% and 100%, respectively. Boost contamination of hamburger samples with E. coli O157 bacteria which are exposedto low microbial quality of raw meat samples and also unfitness of cooking time and temperature. Thoughtful antibiotic prescription and courtesies to the ideologies of food security can condense the hazard of resistant and virulent E. coli O157 in hamburger.