Escherichia coli productor de toxina Shiga en carnes molidas y chacinados embutidos de Corrientes, Argentina

Abstract

Shiga toxin-producing Escherichia coli (STEC) causes sporadic outbreaks of non-bloody and bloody diarrhea, and hemolytic uremic syndrome (HUS). E. coli O157:H7 is the most prevalent STEC serotype. However, other serotypes such as O26:H11; O103:H2; O111:NM; O121:H19 and O145:NM may cause a similar disease spectrum. Ruminants, especially cattle, and their beef products, are the most important reservoirs of STEC. From October 2006 to November 2008, two hundred and forty six samples (206 minced beef and 40 sausages) were analysed bacteriologically. After biochemical characterization of E. coli, multiplex PCR was performed in order to detect stx1/stx2 and rfbO157 genes. PCR was carried out to determine additional virulence factors such as eae and exhA. One hundred and seventy two E. coli strains were identified (139 from 88 minced beef samples and 33 from 19 sausages), one STEC O174:H21, stx2 +, exhA +, eae - and one non-toxigenic O157:NM, eae and ehxA negatives were isolated from minced beef samples. Strains stx2 are predominant in cattle and swine in Argentina, especially in their derivates such as minced beef and hamburgers.