Serotypes, virulence profiles and stx subtypes of Shigatoxigenic Escherichia coli isolated from chicken derived products.

Shigatoxigenic Escherichia coli (STEC) is a foodborne pathogen that causes hemolytic uremic syndrome (HUS) and the consumption of chicken products has been related to some HUS cases. We performed a non-selective isolation and characterization of STEC strains from retail chicken products. STEC isolates were characterized according to the presence of stx1, stx2, eae, saa and ehxA; stx subtypes and serotypes. Most of them carried stx2, showing subtypes associated with severe human disease. Although reported in other avian species, the stx2f subtype was not detected. The isolates corresponded to different serotypes and some of them, such as O22:H8, O113:H21, O130:H11, O171:H2 and O178:H19, have also been identified among STEC isolated from patients suffering from diarrhea, hemorrhagic colitis, HUS, as well as from cattle. Considering the virulence profiles and serotypes identified, our results indicate that raw chicken products, especially hamburgers sold at butcheries, can be vehicles for high-risk STEC strains.