Wibawa I Dewa Nyoman, Suryadarma I G A, Tsuda Fumio, Matsumoto Yasunobu, Ninomiya Masashi, Takahashi Masaharu, Okamoto Hiroaki
Division of Gastroenterology and Hepatology, Department of Internal Medicine, Sanglah Hospital of Udayana University, Denpasar, Bali, Indonesia.
J Med Virol. 2007 Aug;79(8):1138-46. doi: 10.1002/jmv.20904.
A previous study revealed that antibodies to hepatitis E virus (HEV) (anti-HEV) are highly prevalent among healthy individuals and farm pigs in Bali, Indonesia, and suggested that HEV infection may occur via zoonosis among Balinese people. However, there were no reports of acute hepatitis E in Bali. To elucidate whether Balinese HEV strains recovered from infected humans and pigs have significant sequence similarity, serum samples obtained from 57 patients (age, mean +/- standard deviation, 31.1 +/- 11.9 years) with sporadic acute hepatitis and from one hundred and one 2- or 3-month-old farm pigs in Bali were tested for anti-HEV and HEV RNA. Among the 57 patients, 2 (3.5%) had high-titer IgM/IgA class anti-HEV antibodies and one of them had detectable HEV RNA (BaliE03-46). Overall, 58 pigs (57.4%) tested positive for anti-HEV, while 5 pigs (5.0%) had detectable HEV RNA. Based on the 412-nucleotide sequence within open reading frame 2, the BaliE03-46 isolate and the 5 swine HEV isolates recovered from the viremic pigs were phylogenetically classified in genotype 4, but were only 77.3-90.8% identical to the genotype 4 HEV isolates reported thus far in China, India, Japan, Taiwan, and Vietnam. The BaliE03-46 isolate of human origin shared high identities of 97.3-98.3% with 4 of the 5 Balinese swine isolates, but differed by 16.1% from the remaining swine isolate. These results suggest that indigenous HEV strains of genotype 4 with marked heterogeneity are circulating in Bali, Indonesia, and that pigs are reservoirs of HEV for Balinese people who have a habit of ingesting uncooked pigs.
先前的一项研究表明，在印度尼西亚巴厘岛的健康个体和农场猪中，戊型肝炎病毒（HEV）抗体（抗-HEV）高度流行，并提示HEV感染可能通过人畜共患病在巴厘岛人群中发生。然而，巴厘岛尚无急性戊型肝炎的报告。为了阐明从感染人类和猪中分离出的巴厘岛HEV毒株是否具有显著的序列相似性，对57例散发性急性肝炎患者（年龄，平均±标准差，31.1±11.9岁）以及巴厘岛101头2至3月龄农场猪的血清样本进行了抗-HEV和HEV RNA检测。在这57例患者中，2例（3.5%）具有高滴度IgM/IgA类抗-HEV抗体，其中1例可检测到HEV RNA（BaliE03-46）。总体而言，58头猪（57.4%）抗-HEV检测呈阳性，而5头猪（5.0%）可检测到HEV RNA。基于开放阅读框2内的412个核苷酸序列，从病毒血症猪中分离出的BaliE03-46毒株和5株猪HEV毒株在系统发育上被归类为基因型4，但与迄今在中国、印度、日本、台湾和越南报告的基因型4 HEV毒株的同一性仅为77.3-90.8%。源自人类的BaliE03-46毒株与5株巴厘岛猪分离株中的4株具有97.3-98.3%的高度同一性，但与其余猪分离株相差16.1%。这些结果表明，具有明显异质性的基因型4本土HEV毒株在印度尼西亚巴厘岛流行，并且猪是有生食猪肉习惯的巴厘岛人群的HEV储存宿主。
