Department of Infectious Diseases, College of Veterinary Medicine, Konkuk University, Seoul, Korea.
J Med Virol. 2010 Apr;82(4):583-91. doi: 10.1002/jmv.21730.
The hepatitis E virus (HEV) is an emerging zoonotic agent, for which pigs are the most important reservoir. Complete genome sequences of two swine HEV strains, designated swKOR-1 and swKOR-2, were determined via RT-PCR and RACE-PCR. The strains contained genomes composed of 7,222- and 7,221-bp excluding the poly(A) tails, respectively. The swKOR-1 and swKOR-2 strains were classified into subtype 3a of genotype 3 via phylogenetic analysis. These strains formed a distinctive cluster in the phylogenetic tree with human and swine HEVs isolated in the USA and human HEVs isolated in Japan. Anti-HEV antibodies were identified via ELISA in 8 of 99 (8.1%) cats, whereas, among 115 cattle and 213 dogs, no HEV-specific antibodies were detected. The conserved RNA-dependent RNA polymerase (RdRp) gene of HEV could be detected via RT-PCR in 8.7% of raw oysters collected from coastal regions in Korea. The HEV RNAs detected in oysters were identified as belonging to subtype 3a. The HEV RNAs in oysters most closely resembled that of the swKOR-2 strain. They also showed a close genetic relationship with the swKOR-1 strain and the swine and human HEVs isolated in the USA. This is the first report describing the detection in oysters of HEV that may have originated from genotype 3 swine HEV in Korea. Pigs and cats infected with HEV, as well as oysters contaminated with HEV, are potential risk factors for HEV transmission to humans.
戊型肝炎病毒(HEV)是一种新兴的人畜共患病原体,猪是其最重要的储存宿主。通过 RT-PCR 和 RACE-PCR,确定了两株猪源 HEV 株(swKOR-1 和 swKOR-2)的完整基因组序列。这两个毒株的基因组分别由 7222 个和 7221 个核苷酸组成,不包括 poly(A)尾巴。通过系统进化分析,swKOR-1 和 swKOR-2 株被归为 3 型的 3a 亚型。这些毒株在系统进化树上与美国分离的人和猪源 HEV 以及日本分离的人源 HEV 形成一个独特的聚类。通过 ELISA 检测,在 99 只猫中有 8 只(8.1%)检测到抗 HEV 抗体,而在 115 头牛和 213 只狗中未检测到 HEV 特异性抗体。通过 RT-PCR 可以在韩国沿海地区采集的 8.7%的生牡蛎中检测到 HEV 的保守 RNA 依赖性 RNA 聚合酶(RdRp)基因。在牡蛎中检测到的 HEV RNA 被鉴定为属于 3a 亚型。牡蛎中检测到的 HEV RNA 与 swKOR-2 株最为相似,与 swKOR-1 株以及美国分离的猪源和人源 HEV 也具有密切的遗传关系。这是首次报道在韩国牡蛎中检测到可能源自基因型 3 猪源 HEV 的 HEV。感染 HEV 的猪和猫以及受 HEV 污染的牡蛎,都是 HEV 传播给人类的潜在危险因素。