Shiga-Toxigenic Escherichia coli in Sheep Cheeses

The relationship between the presence of Escherichia coli in food products and occurrence of food infections and poisonings have been confirmed in various studies. Among them، milk and dairy products have the high importance. This present study was carried out in order to study the presences of Escherichia coli، Escherichia coli O157: H7 and shiga-toxin producing Escherichia coli in cottage cheese. Totally، 110 cottage cheese samples were collected from Isfahan province’s retailers. The cheese samples were produced from raw sheep milk. All samples were transferred to the laboratory and were studied using the microbial culture and Polymerase Chain Reaction. From a total of 110 cheese samples، 23 samples were positive for presence of Escherichia coli while none of them were not Escherichia coli O157: H7. From these 23 positive samples، 2 samples had stx1 (8. 69%)، 1 samples had stx2 (4. 34%)، 3 samples had eaeA (13. 04%) and finally 1 sample had ehxA (4. 34%) virulence genes. In the other hands، the vt1 and vt2 genes were not detected in any sample. This study showed that using from unpasteurized and cottage cheese can be dangerous for human health. We recommended using PCR as an accurate، safe and rapid method in order to control the microbial quality of raw dairy products.