Objectives: To investigate HEV infection in swine and the genotype relationship between swine and human HEV.
Methods: Anti-HEV IgG antibody was detected in the sera of swine using enzyme linked immunoassay (EIA), and HEV RNA was amplified by reverse transcription nested polymerase chain reaction (RT-nPCR). The Vector NTI Suite 7 and TreeView softwares were used for nucleotide sequences phylogenetic analysis of HEV isolated from human and swine.
Results: The anti-HEV IgG positive rate was 16.67% (18/108). Among the 18 anti-HEV IgG positive sera, 2 sequences (11.11%, called S18 and S43, respectively) of HEV ORF1 (102-387bp) were amplified, with the identity of 99% between them. They had 76% to 77%, 78%, 76% to 79%, 85% to 86%, 77%, 80%, 79% and 75% - 79% homology at the nucleotide level with human HEV genotypes 1 to 8, respectively. One (S18) of them was also amplified out in ORF2 region (5,994-6 297bp) and showed 76% to 78%, 74%, 74% to 77%, and 85% to 94% identity with human HEV genotypes 1 to 4 at the nucleotide level, respectively.
Conclusion: HEV sequences isolated from swine belong to human HEV genotype 4.