Hepatitis E virus infection in farmed rabbits and swine in the Eastern Chinese city Lianyungang: showing no potential interspecies transmission.

Rabbit HEV isolated recently from farmed rabbits in China has been shown experimentally to be able to infect both cynomolgus macaques and pigs. The purpose of the present study was to investigate the extent to which cross-species transmission of rabbit HEV in farm settings is a significant factor in the spread of this zoonotic infection. Rabbit and swine feces were collected from the same area in Eastern China (Lianyungang City) and analyzed by RT-PCR. Partial genome sequencing of a 365 bp region of ORF2 from the HEV positive rabbit samples revealed that they had 92-99% sequence identity with rabbit strains (rbIM163-c1 and rbIM004) isolated from Inner Mongolia. Similarly, sequencing of a 765 bp region of ORF2 of HEV positive swine samples showed 96-98% sequence identity with genotype 4d isolates collected from patients in the Yantai and Nanjing regions of China. By contrast, the sequence identity between the rabbit and swine isolates was only 73-75%, with no molecular biological evidence of interspecies transmission having occurred. It is concluded that whilst interspecies infection with rabbit HEV can be achieved experimentally, in the field it is not a significant factor in zoonotic disease transmission at least in the area of China where this study was undertaken.