Wu J C, Chen C M, Chiang T Y, Sheen I J, Chen J Y, Tsai W H, Huang Y H, Lee S D
Institute of Clinical Medicine and Division of Gastroenterology, Veterans General Hospital, National Yang-Ming University School of Medicine, Taipei, Taiwan.
J Med Virol. 2000 Feb;60(2):166-71.
In nonendemic areas, most patients with acute hepatitis E were infected through traveling to endemic areas. However, some patients did not have a history of foreign travel before infection. Furthermore, high seroprevalence rates of antibody to hepatitis E virus (anti-HEV) were found in the general adult population in some countries without any recorded outbreak of hepatitis E. The significance of anti-HEV assay in these subjects remains obscure. To study if swine might be a source of HEV infection, HEV was tested in sera of 235 pigs in Taiwan, and from 5 patients with acute HEV infection who either denied or did not provide any foreign travel history. Three (1.3%) pigs had detectable swine HEV RNA. The swine and human HEV strains from Taiwan formed a monophyletic group, distinct from three previously reported groups: the United States human and swine HEV strains, the Mexico strain, and the largest group composed of the Asian and the African strains. The identity of nucleotide sequences was 84-95% between swine and human HEV strains in Taiwan, and 72-79% between Taiwan strains and those from different areas. The predicted amino acid sequence of a Taiwan swine HEV strain within the peptide 3-2 used in commercial anti-HEV assay showed a high identity (91-94%) with those of other human and swine HEV strains. Swine may be a reservoir of HEV and subclinical swine HEV infection may occur. Cross-reactivity of current anti-HEV assay may account for the high prevalence rate of anti-HEV in the general population in nonendemic areas.
在非流行地区，大多数急性戊型肝炎患者是通过前往流行地区而感染的。然而，一些患者在感染前并无国外旅行史。此外，在一些没有戊型肝炎疫情记录的国家，普通成年人群中戊型肝炎病毒抗体（抗 - HEV）的血清阳性率较高。抗 - HEV检测在这些人群中的意义仍不明确。为研究猪是否可能是戊型肝炎病毒感染源，对台湾235头猪的血清以及5例急性戊型肝炎感染患者（这些患者否认或未提供任何国外旅行史）的血清进行了戊型肝炎病毒检测。3头猪（1.3%）检测到猪戊型肝炎病毒RNA。台湾的猪和人戊型肝炎病毒株形成一个单系群，与之前报道的三个群不同：美国的人和猪戊型肝炎病毒株、墨西哥株，以及由亚洲和非洲株组成的最大群。台湾猪和人戊型肝炎病毒株之间核苷酸序列的同一性为84 - 95%，台湾株与来自不同地区的毒株之间为72 - 79%。在商业抗 - HEV检测中使用的肽段3 - 2内的台湾猪戊型肝炎病毒株预测氨基酸序列与其他人和猪戊型肝炎病毒株显示出高度同一性（91 - 94%）。猪可能是戊型肝炎病毒的储存宿主，可能发生亚临床猪戊型肝炎病毒感染。目前抗 - HEV检测的交叉反应性可能是导致非流行地区普通人群中抗 - HEV高流行率的原因。
