Comparative evaluation of stx-PCR, Vero cell assay and Verotoxin enzyme imminoassay for detection of Shiga toxin-producing Escherichia coli]

To evaluate the suitability of stx-PCR, Vero cell assay and commercial enzyme immunoassay for detection of Shiga toxin Escherichia coli and to compare sensitivity and specificity of three different methods for detection of Shiga toxin-producing Escherichia coli.Using stx-PCR, Vero cell assay and commercial enzyme immunoassay to detect 35 Escherichia coli reference strains and 45 strains isolated from food.The three methods all had good specificity. 31 strains gave positive reaction in the Vero cell assay and in the stx-PCR. The consistency between the Vero cell assay and stx-PCR was 100%. Only 38 strains can be detected by commercial enzyme immunoassay.stx-PCR method can serve as a routine rapid detection method in the laboratory. Vero cell assay is recommended to be the gold standard to determine whether the bacteria had the functionally active toxin. Commercial kit was suitable for preliminary rapid detection during clinical testing and outbreaks of food-borne disease.