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Objective: To determine the genotype and phylogenetic characteristics of hepatitis E virus (HEV) strains isolated from the human and swine in Anqing City., Methods: Twenty seven sera from sporadic hepatitis E patients and 400 commercial swine bile samples were collected in Anqing City. According to the collection time, the bile samples were equally divided into 4 groups which were named group A, B, C and D respectively. Nested reverse transcription polymerase chain reaction (RT-PCR) and DNA sequencing technology were performed to obtain the DNA sequences of HEV RNA Open Reading Frame 2 (ORF2) (150 nt) for all the serum and bile samples. The sample sequences and prototype sequences from the GenBank were aligned and their nucleotide sequence identities were calculated. A phylogenetic tree constructed according to the Bayesian inference method was used to analyze the genotype and phylogenetic relationship between the human and swine HEV strains isolated in Anqing City., Results: The male-to-female sex ratio of the patients was 2.86:1 and the average age was 56.78 years old. Sixteen out of 27 serum (59.26%) samples were HEV RNA positive. Human HEV strains isolated in Anqing City shared 74.75% - 82.99%, 75.26% - 83.64%, 72.77% - 80.57% and 88.03%-91.63% nucleotide sequence identities with prototype I, II, III and IV HEV strains respectively. HEV RNA was detected in 22 out of 400 bile samples (5.5%). The swine HEV detection rates for group A, B, C and D were 7.00%, 3.00%, 9.00% and 3.00% respectively, showing no significant difference among these groups (χ(2) = 5.20, P = 0.16). Swine HEV strains isolated in Anqing City shared 75.24% - 83.42%, 75.93% - 84.19%, 72.86% - 80.64% and 88.15% - 91.79% nucleotide sequence identities with prototype I, II, III and IV HEV strains respectively. Phylogenetic analysis revealed that all the HEV strains isolated from both the human and swine belonged to genotype IV and scattered in evolutionary branches without significant species aggregation., Conclusion: It's suggested that genotype IV HEV was the dominant genotype among the human and swine in Anqing City and probably transmitted between them in this area.

Objective: To determine the prevalence and genotype of hepatitis E virus (HEV) among commercial swine population in Eastern and Southern China., Methods: Six hundred specimens of swine bile collected from 5 slaughterhouses in Eastern and Southern China from 2007 to 2009 were tested for HEV RNA using nested RT-PCR. PCR products were sequenced for phylogenetic analysis., Results: Forty-seven out of the 600 samples (7.83%) were positive for HEV RNA. Based on the 150 nt fragment within HEV ORF2, data from phylogenetic analysis revealed that all the 47 HEV isolates were identified to be genotype IV, sharing 75.0% - 83.4%, 75.0% - 84.6%, 71.9% - 80.7% and 88.1% - 91.5% nucleotide identities with prototype I, II, III and IV HEV strains respectively while majority of the isolates clustered within their respective isolation sites., Conclusion: HEV was widespread in commercial swine population in Eastern and Southern China that raised a serious concern about the safety regarding the consumption of pork products.

Hepatitis E has been hypothesized as a zoonosis. However, there is no definite conclusion about which animal species contribute to hepatitis E virus (HEV) infection in humans. In this study, HEV RNA was detected only in swine bile specimens and not in bile specimens collected from cattle, goats, or dogs. We postulate that swine are the main animal reservoir for HEV.

Objective: To study the genotype of swines isolated from humans and their relationships with hepatitis E virus (HEV) in the rural areas of southern China., Methods: Specimens collected from normal people with HEV-IgM positive, acute hepatitis E patients and from swine in the same area were detected for HEV RNA using RT-nPCR with ORF2 primers. The positive PCR products were cloned and sequenced., Results: 13 out of the 132 samples from swine stool, 4 of 26 HEV-IgM positive sera of normal people and 1 of 4 acute hepatitis E patients' stool sample and sera were tested positive for HEV RNA. Data from sequence analysis showed that the identity at nucleotide level was 89.3%-100.0% among the 10 isolates which shared 78.7% - 84.7%, 83.3% - 85.3%, 76.0% - 80.0% and 84.7% - 95.3% nucleotide sequence identity with HEV genotype I, II, III and IV respectively in the region (nt6317- 6466)., Conclusion: HEV circulating in humans and swine in the area belonged to genotype IV.