Monitoring pathogenic Escherichia coli in Alberta beef cattle

Shiga toxin-producing Escherichia coli (STEC) are human pathogens responsible for deadly outbreaks throughout the world. Cattle are the primary reservoir for these pathogens, secreting STEC in the feces. Bovine feces is the principal source of contamination of food products, however detection of STEC in feces has several inherent limitations. The objectives of this study were to develop and refine detection methods for STEC in cattle feces. Multiplex PCRs for detection of STEC serogroups and virulence genes were designed. Serogroup detection in feces significantly improved with enrichment (10 CFU/g feces). However, isolation of target serogroups from feces remains challenging, and additional refinements to immunomagnetic separation (IMS) techniques would be an asset. Novel techniques for detection and isolation of STEC across the farm-to-fork spectrum will continue to improve food safety monitoring and reduce risks to human health by decreasing circulation of contaminated products, aiding in diagnostics, and supporting outbreak management