Molecular epidemiology of hepatitis E virus in Japan and study on animal host of virus.

我对来自11个国家的5，233份血清中的戊型肝炎病毒（HEV）抗体流行率进行了血清流行病学研究，以确定全球HEV感染的现状。抗-HEVIgG阳性率：日本东京8.9%，冲绳34.5%，越南河内62.1%，胡志明市41.8%，中国哈尔滨29.2%，泰国27%，缅甸35.1%，尼泊尔66%，美国21.3%，西班牙34%，俄罗斯20.2%，埃及80%，玻利维亚12.7%。抗-HEVIgG抗体阳性率随年龄增长而增加，但除日本、美国和西班牙外，16-30岁年龄组抗体阳性率均在20%以上。来自尼泊尔的病因不明的急性肝炎患者中，56%（14/25）的抗-HEV抗体IgM类阳性。另外，用巢式PCR方法检测了3例尼泊尔人血清中的HEV RNA，均为1型。我们的研究结果表明，HEV不仅在发展中国家，而且在工业化程度更高的国家也在全球范围内传播。

I conducted seroepidemiological studies on antibody prevalence to hepatitis E virus (HEV) in 5,233 sera from 11 countries to ascertain the present state of HEV infection on a global basis. The rate of anti-HEV IgG positivity was as follows : 8.9% in Tokyo and 34.5% in Okinawa of Japan, 62.1% in Hanoi and 41.8% in Ho Chi Minh City of Vietnam, 29.2% in Harbin of China, 27% in Thailand, 35.1% in Myanmar, 66% in Nepal, 21.3% in U.S.A., 34% in Spain, 20.2% in Russia, 80% in Egypt and 12.7% in Bolivia, respectively. The prevalence of anti-HEV IgG increased with age in these tested countries, but the rate of antibody positivity was over 20% in the 16-30 year-old group in most of the participating countries, except for Japan, the U.S.A and Spain. Of patients with acute hepatitis of unknown etiology from Nepal, 56% (14/25) were positive for the IgM class of anti-HEV antibody. In addition, HEV RNAs in the serum from 3 Nepali patients who had the IgM antibody were detected by nested PCR and all of the HEV genes isolated belonged to genotype, 1. Our results indicate that HEV is spreading worldwide not only in developing countries, but also in more industrialized countries than previously thought.