A.M.P. de Almeida and N.C. Leal (eds.), Advances in Yersinia Research, Advances in Experimental Medicine and Biology 954, DOI 10.1007/978-1-4614-3561-7_14
Enteroinvasive pathogenic strains of Yersinia enterocolitica are recognized as major human pathogens that cause 96,000 cases of human disease annually in the United States (Scallen et al. 2011 ) . Ninety percent of those cases are the result of foodborne transmission (Centers for Disease Control and Prevention (CDC) 2006 ; Nesbakken 2005 ; Scallen et al. 2011 ) . Swine are identified as important reservoirs of Y. enterocolitica serotypes (O:3, O:5, O:8, O:9) that are associated with human illness (Fredriksson-Ahomaa et al. 2011 ) . Pathogenic Y. enterocolitica carriage in swine ranges from 35 to 70% of herds and 4.5 to 100% of individual pigs (Ortiz Martinez et al. 2009 ). Y. enterocolitica is transmitted among swine by the oral–fecal route and is found on the surface of freshly slaughtered pig carcasses. This is likely the result of the spread of feces or contamination from the oral cavity during the slaughtering process (Laukkanen et al. 2009) . In the United States, few studies on the prevalence of Y. enterocolitica in swine have been conducted (Bhaduri 2001 ; Bhaduri and Wesley 2006 ; CDC 2006, 2011 ).