Phylogenetic analysis of hepatitis E virus strains isolated from both human and swine in Anqing City / 中华预防医学杂志

<p><b>OBJECTIVE</b>To determine the genotype and phylogenetic characteristics of hepatitis E virus (HEV) strains isolated from the human and swine in Anqing City.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>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.</p>

Study on the prevalence and genotype of hepatitis E virus among commercial swine population in Eastern and Southern China / 中华流行病学杂志

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.

Phylogenetic analysis of sporadic hepatitis E virus in Eastern China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand phylogenetic characteristics of sporadic hepatitis E virus (HEV) in eastern China.</p><p><b>METHODS</b>Four hundred and thirteen sera were collected from sporadic hepatitis E cases in 14 second- or first-class hospitals in Eastern China from 2005 to 2008 and detected with a nested RT-PCR assay. Partial nucleotide sequences of the HEV isolates were determined for phylogenetic analysis with prototype sequences in the GenBank.</p><p><b>RESULTS</b>The male-to-female sex ratio of the patients was 1.75:1 with 61.5% of them aged 40 - 69 years old. HEV RNA was detected in 140 out of 413(34%)serum samples. Phylogenetic analysis revealed that all the 140 HEV isolates belonged to genotype IV, sharing 77.9% - 88.3%, 80.8% - 90.6%, 73.4% - 85.2% and 91.0% - 95.4% nucleotide sequence identities with prototype I, II, III and IV HEV isolates respectively.</p><p><b>CONCLUSION</b>It was evident that genotype IV HEV served as the main causative agent of sporadic HEV infection in Eastern China. However the viral origin and evolution needs further clarification.</p>