Cattle and other ruminants are primary reservoirs for Shiga toxin-producing Escherichia coli (STEC) strains which have a highly variable, but unpredictable, pathogenic potential for humans. Domestic swine can carry and shed STEC, but only STEC strains producing the Shiga toxin (Stx) 2e variant and causing edema disease in piglets are considered pathogens of veterinary medical interest. In this chapter, we present general diagnostic workflows for sampling livestock animals to assess STEC prevalence, magnitude, and duration of host colonization. This is followed by detailed method protocols for STEC detection and typing at genetic and phenotypic levels to assess the relative virulence exerted by the strains.
Keywords: Adhesion assay; ELISA; Host–cell interactions; Invasion assay; Multilocus sequence typing; PCR; Prevalence; Pulsed-field gel electrophoresis; STEC; Shiga toxin; Shiga toxin-producing Escherichia coli; Vero cell cytotoxicity assay; Virulence genes.