Detection of Escherichia coli O157 in French food samples using an immunomagnetic separation method and the VIDASTME. coli O157

C. VERNOZY-ROZAND, C. MAZUY, S. RAY-GUENIOT, S. BOUTRAND-LOEï, A. MEYRAND AND y. richard. 1997. Two commercially available screening methods, an automated enzyme-linked fluorescent immunoassay (VIDAS^TM E. coli O157) and an immunomagnetic separation followed by culture onto cefixime tellurite sorbitol MacConkey agar (CT-SMAC), were compared for detection of Escherichia coli O157 in naturally and artificially contaminated food samples. A total of 250 naturally contaminated food samples, including raw milk cheeses, poultry, raw sausages and ground beef retail samples, were examined. Four poultry, one raw sausage and one ground beef sample were found to be positive for E. coli O157 by both methods. Of the six positive samples, five were shown to contain sorbitol-positive, O157-positive, H7-negative, motile and non-verotoxin-producing E. coli .