Detection of Escherichia coli O157:H7 using immunomagnetic separation and mPCR in Turkish foods of animal origin.

UNLABELLED: The present study was conducted to investigate the presence of Escherichia coli O157:H7 in food samples of animal origin and to detect its virulence genes by immunomagnetic separation technique and multiplex PCR (mPCR). A total of 500 samples (consisting of diced meat, minced meat, burger, raw cow's milk and raw cow's milk cheese) were analysed. Escherichia coli O157:H7 was detected in 5 (1%) of 500 analysed samples including two diced meat, one minced meat and two raw-milk cheese. None of the burger samples tested contained E. coli O157:H7. Three isolates obtained from minced and diced meat were found to carry stx1 , stx2 , hlyA and eaeA genes whereas two isolates from raw-milk cheese were found to harbour the stx1 , eaeA and hlyA genes. The results of this study suggest that raw meat and raw-milk cheese tested could pose public health problems in consumers with regard to their virulence factors. SIGNIFICANCE AND IMPACT OF THE STUDY: Escherichia coli (E. coli) O157:H7 is an important human pathogen. Escherichia coli 0157:H7 infections have been associated with consumption of uncooked meat and meat products, as well as unpasteurized dairy products. This study demonstrated that without specific tests for E. coli virulence factors raw meat and raw-milk cheese could pose public health problems to Turkish consumers.