Genotyping of Escherichia coli O157: H7 strains isolated from raw ruminant and poultry meat samples by RAPD-PCR

Escherichia coli O157:H7 is one of the most important enteric pathogenic strains that is usually transmitted to humans through contaminated water and food. These strains cause hemorrhagic colitis, HUS syndrome, cytopenic purpura thrombosis, and, in some cases, death. The main repository of these bacteria is ruminants. The aim of this study was genetic classification (genotyping) of isolates of this strain isolated from raw meat and poultry by RAPD-PCR method. 344 samples of ruminants and poultry were collected from fresh meat supply centers in Isfahan and Shahrekord. Genetic classification of O157:H7 isolates was performed by the RAPD-PCR method. Of 344 raw meat samples studied, 202 Escherichia coli isolates (58.7%) were isolated. The rate of O157: H7 strain was 17.8% (36 samples). Genetic classification of Escherichia coli O157:H7 isolates showed 9 different profiles among these 36 isolates and found an affinity of 43.7 to 100% among the isolates. This study showed high molecular similarity between E. coli O157: H7 strains isolated from different animals in Isfahan and Shahrekord. It was also found that RAPD-PCR is a simple, fast, and inexpensive method for describing the genetic diversity of different E. coli strains including strain O157:H7.