Detection and characterisation of swine hepatitis E virus in New Zealand

The objectives of the present study were to establish the presence of hepat itis E virus (HEV) in New Zealand pigs, first by testing for HEV antibody i n pig herds throughout New Zealand to measure the herd prevalence, then by attempting to amplify HEV genomic sequences by PCR. Antibody was measured b y two independently designed ELISA serology tests. HEV RNA fragments were a mplified by RT-PCR of nucleic acid extracted from faeces of 10-12-week-old piglets using primers targeting ORF1, ORF2, and ORF2/3. PCR products were s ubject to phylogenetic analysis. Antibody to HEV was found throughout New Z ealand pig herds as well as in the different age groups within the herds. T wenty herds from 22 tested were positive for HEV antibody (91% herd prevale nce). Phylogenetic analysis of the amplified sequences placed this New Zeal and strain of HEV closest to the human European strain It-1 (AF 110390) and U.S. swine strain (AF 082843) with 88% and 83% similarity respectively in ORF1. It was concluded that HEV is widely distributed in the New Zealand pi g population. Phylogenetic analysis shows that this is a new HEV strain, gr ouping most closely with the United States/European cluster, which includes HEV strains of both human and swine origin. (C) 2001 Wiley-Liss, Inc.