Prevalence of Antibiotic Resistance and Distribution of Virulence Factors in the Shiga Toxigenic Escherichia coli Recovered from Hospital Food

Background: Regarding the presence of immunosuppressed patients in hospitals, hospital food must have a boost safety. Escherichia coli O157 is one of the prevalent causes of food-related poisoning.Objectives: The current examination was done to assess the distribution of virulence factors and phenotypic analysis of antibiotic resistance of E. coli O157 bacteria recovered from hospital food.Methods: From April to August 2016, 200 hospital food samples were obtained and directly transported to the laboratory. Escherichia coli O157-positive bacteria were analyzed by disk diffusion and polymerase chain reaction (PCR).Results: Nine out of 200 (4.50%) samples harbored E. coli O157. Distribution of E. coli O157 in soup and gavage samples were 3% and 6%, respectively. Stx1 (100%), eaeA (100%), and ehlyA (100%) were the most frequently detected virulence genes. Escherichia coli O157 bacteria exhibited maximum prevalence of antibiotic resistance against tetracycline (100%), gentamycin (100%), ampicillin (100%), mezlocillin (50%), enrofloxacin (50%), and trimethoprim (50%). Distribution of resistance of E. coli O157 bacteria against more than six antibiotic agents was 11.11%.Conclusions: Gavage and soup samples may be sources of virulent and resistant E. coli O157. High presence of E. coli O157, simultaneous presence of multiple virulence genes, and resistance against animal-based antibiotics presented inadequacy of cooking time and temperature in processing of hospital foods.