<OL> <LI> Identify sources of primary infection by EHEC. Objective achievement will result in knowledge of when and how livestock are initially infected by this pathogen. This data is required to effectively prevent infections from occuring. <LI> Identify host response correlates of infection, carriage and clearance of EHEC. Rational preventive strategies should be based on a clear understanding of what host and agent responses are associated with clearance of infection or prolonged carriage of the pathogen.
Enterohemorrhagic Escherichia coi (EHEC) are the most important zoonotic food-borne bacterial pathogens of livestock from public health, agricultural, and economic viewpoints. It is documented that pre-harvest (live animal) fecal pathogen prevalence correlates positively with post-harvest (carcass surface) prevalence for EHEC O157. Therefore, it is rationale to identify livestock with high pre-harvest pathogen prevalence and attempt to lower this prevalence prior to presentation for slaughter. Achievement of these objectives will provide a rational foundation for implementing (or not implementing) pre-harvest control efforts (I.e., food-borne pathogen prevalence reduction) in livestock intended for use as food. In essence, our goal is to determine if, how, and when to reduce EHEC pre-harvest pathogen prevalence. MARC,Clay Center, NE, Building 19, Laboratories 150, 153, and 156. Laboratories 153 and 156 are BL-3 capable, while Laboratory 150 is BL-2; #978. Certified April 17, 2001.