Surveillance of Hepatitis E virus (HEV) in swine farms and farmers and first identification of genotype 4 in Italy.

Abstract Hepatitis E is an emerging zoonotic disease caused by a positive ssRNA virus, Hepatitis E virus (HEV). In Europe, pigs are the main reservoir. Genotype 3 of HEV (HEV3) has a worldwide distribution while genotype 4 (HEV4) mostly occurs in Asia. However, HEV4 has recently been isolated in pigs and humans in Europe. Abstract methods During 2011-2014, a monitoring plan was performed to evaluate the prevalence of HEV infection in different human populations and pigs in Italy. Assuming an expected herd-level seroprevalence of 50%, 175 pig farms were sampled. To detect at least one positive sample assuming a within-herd seroprevalence of 30%, 9 sera were collected and analyzed from each farm. Moreover, in 105 farms HEV presence was investigated collecting 10 fecal pools. In order to understand whether consumption of pork products or/and contact with pigs may represent a risk factor, sera were collected from farmers (no.127), general population(no.131) and vegetarian/vegan group (no.114). Abstract results Anti-HEV antibodies were detected in 65.7% (115/175,95% CI:58.2-72.7) of farms, while viral RNA was identified in 24.8% (26/105). Most of the identified strains belonged to HEV3. However, in one farm HEV4 was detected. HEV seroprevalence in humans was significantly different among the 3 groups (p