Prevalence of Hepatitis E Virus Infection in Pigs at the Time of Slaughter, United Kingdom, 2013

Since 2010, reports of infection with hepatitis E virus (HEV) have increased in England and Wales. Despite mounting evidence regarding the zoonotic potential of porcine HEV, there are limited data on its prevalence in pigs in the United Kingdom. We investigated antibody prevalence, active infection, and virus variation in serum and cecal content samples from 629 pigs at slaughter. Prevalence of antibodies to HEV was 92.8% (584/629), and HEV RNA was detected in 15% of cecal contents (93/629), 3% of plasma samples (22/629), and 2% of both (14/629). However, although HEV is prevalent in pigs in the United Kingdom and viremic pigs are entering the food chain, most (22/23) viral sequences clustered separately from the dominant type seen in humans. Thus, pigs raised in the United Kingdom are unlikely to be the main source of human HEV infections in the United Kingdom. Further research is needed to identify the source of these infections.