Primadharsini Putu Prathiwi, Miyake Masao, Kunita Satoshi, Nishizawa Tsutomu, Takahashi Masaharu, Nagashima Shigeo, Ohnishi Hiroshi, Kobayashi Tominari, Nishiyama Takashi, Jirintai Suljid, Okamoto Hiroaki
Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke-Shi, Tochigi-Ken 329-0498, Japan.
Animal Biosecurity Consulting Inc., 3-25-29 Natsumidai, Funabashi-Shi, Chiba-Ken 273-0866, Japan.
Virus Res. 2017 Aug 15;240:147-153. doi: 10.1016/j.virusres.2017.08.003. Epub 2017 Aug 16.
Hepatitis E virus (HEV) causes acute or chronic hepatitis in humans and can be transmitted via the fecal-oral route. Pigs are one of the main reservoirs for this infection. Sixty pigs, 4-5 months of age, on a swine herd in Japan had detectable anti-HEV IgG antibodies, and five (8.3%) of them had ongoing infection of genotype 3 HEV. Five HEV strains obtained from the viremic pigs shared 98.8-100% nucleotide identity, and one representative strain (swHE1606845), whose entire genomic sequence was determined in this study, differed by 14.1-19.6% from the reported HEV strains of subtypes 3a-3k and by 14.7-19.1% from other genotype 3 HEV strains whose subtypes have not yet been assigned. swHE1606845 showed a higher nucleotide p-distance value of ≥0.143 with the genotype 3 HEV strains of subtypes 3a-3k and ≥0.152 with other genotype 3 strains of unassigned subtypes. A SimPlot analysis revealed a lack of recombination events. These results indicate that swHE1606845 is a candidate member of a novel subtype of genotype 3. Further efforts to identify the swHE1606845-like novel strain are warranted to clarify the origin of this strain and to determine the complete nucleotide sequences of two additional swHE1606845-like strains for assigning a new subtype.
戊型肝炎病毒（HEV）可导致人类急性或慢性肝炎，且可通过粪-口途径传播。猪是这种感染的主要宿主之一。日本一个猪群中的60头4至5月龄猪可检测到抗HEV IgG抗体，其中5头（8.3%）存在3型HEV的持续感染。从病毒血症猪中获得的5株HEV毒株核苷酸同一性为98.8 - 100%，本研究确定了其完整基因组序列的一个代表性毒株（swHE1606845），与已报道的3a - 3k亚型HEV毒株相比，差异为14.1 - 19.6%，与其他尚未分型的3型HEV毒株相比，差异为14.7 - 19.1%。swHE1606845与3a - 3k亚型的3型HEV毒株核苷酸p距离值≥0.143，与其他未分型的3型毒株核苷酸p距离值≥0.152。SimPlot分析显示不存在重组事件。这些结果表明，swHE1606845是3型新亚型的候选成员。有必要进一步努力鉴定类似swHE1606845的新毒株，以阐明该毒株的起源，并确定另外两株类似swHE1606845毒株的完整核苷酸序列，以便确定一个新的亚型。
