Fukuda S, Ishikawa M, Ochiai N, Suzuki Y, Sunaga J, Shinohara N, Nozawa K, Tsuda F, Takahashi M, Okamoto H
Japanese Red Cross Tochigi Blood Center, Tochigi, Japan.
Arch Virol. 2007;152(9):1623-35. doi: 10.1007/s00705-007-0996-z. Epub 2007 May 29.
Hepatitis E is rare in Japan but is occurring more frequently than previously thought. To investigate whether de novo subclinical infection of hepatitis E virus (HEV) has recently increased in Japan, HEV RNA was assayed in serum samples obtained from 4019 Japanese voluntary blood donors with alanine aminotransferase (ALT) of > or =61 IU/l, who are likely to have ongoing HEV infection, during 1991-2006. The overall rates of IgG-class antibody to HEV (anti-HEV IgG), anti-HEV IgM/IgA and HEV RNA among 3185 donors in 2004-2006 were comparable with those among 594 donors in 1998 (5.3 vs. 5.2%, 0.2 vs. 0.5%, and 0.2 vs. 0.3%, respectively). Among blood donors with ALT > or = 201 IU/l in three groups according to the year of blood collection (1991-1995 [n = 156], 1996-1999 [n = 116] and 2004-2006 [n = 61]), there were no appreciable differences in the prevalence of anti-HEV IgG (5.8, 4.3, and 6.6%, respectively), anti-HEV IgM/IgA (1.9, 3.4, and 3.3%, respectively) and HEV RNA (1.3, 3.4, and 3.3%, respectively). The eleven HEV isolates obtained in the present study differed from each other by 1.7-22.8% in the ORF2 sequence and segregated into genotype 3 or 4. The occurrence rate of subclinical infection with divergent HEV strains has essentially remained unchanged during 1991-2006 in Japan.
戊型肝炎在日本较为罕见，但发病率比之前认为的更高。为调查日本近期戊型肝炎病毒（HEV）新发亚临床感染是否有所增加，对1991年至2006年间从4019名丙氨酸转氨酶（ALT）≥61 IU/l的日本自愿献血者采集的血清样本进行了HEV RNA检测，这些献血者可能存在持续性HEV感染。2004年至2006年3185名献血者中，HEV IgG类抗体（抗HEV IgG）、抗HEV IgM/IgA和HEV RNA的总体发生率与1998年594名献血者中的发生率相当（分别为5.3%对5.2%、0.2%对0.5%、0.2%对0.3%）。在根据采血年份分为三组的ALT≥201 IU/l的献血者中（1991年至1995年[n = 156]、1996年至1999年[n = 116]和2004年至2006年[n = 61]），抗HEV IgG的患病率（分别为5.8%、4.3%和6.6%）、抗HEV IgM/IgA（分别为1.9%、3.4%和3.3%）和HEV RNA（分别为1.3%、3.4%和3.3%）无明显差异。本研究获得的11株HEV分离株的ORF2序列彼此相差1.7%至22.8%，并分为基因型3或4。1991年至2006年期间，日本不同HEV毒株亚临床感染的发生率基本保持不变。
