猪群HEV血清抗体调查及一株新的猪HEV ORF2部分基因序列分析

Prevalence of antibodies to swine hepatitis E virus in China and analysis of a novel HEV ORF2 partial sequences in swine

戊型肝炎病毒 (HepatitisEvirus ,HEV)主要引起人的戊型肝炎 ,新近研究发现猪在病毒传播中可能发挥重要作用。本研究对我国部分省区HEV感染血清学调查 ,在被检的 1138份血清中 ,有 6 6 6份 (5 7 5 % )为HEV抗体阳性 ,猪群抗体阳性率随着月龄增长而升高。通过RT_PCR方法从一份猪粪中扩增并克隆了HEVORF2N端主要抗原决定区339bp基因片段 ,序列分析显示 ,该段基因与我国人群HEV基因 4型毒株核苷酸序列同源性为 85 9% ,但氨基酸序列完全一致。这一结果提示我国猪群存在广泛的HEV感染 。

Hepatitis E virus (HEV) causes a non_A non_B hepatitis in human.It was newly identified that swine may play an important role for transmission HEV to human. In the present study, prevalence of serum antibodies in Chinese swine herds to hepatitis E virus was examined.A total of 1158 serum samples of pigs were examined by enzyme immunoassay,in which 666 (57.5 %) samples were identified to be positive to HEV antibody.The seroprevalence was higher in elder pigs than piglets. Partial ORF2 sequence (designed HEV_DQ_1) was recovered from feces of a pig by RT_PCR.The sequence of nucleotides identity between HEV_DQ_1 and AJ272108,a Chinese HEV sequence recovered from human,was only 85.9 %, while the amino sequences were completely identical. This study indicates that HEV is highly prevalent in swine populations in China and swine HEV may have close relationship with human HEV strains.