Motoya Takumi, Umezawa Masahiro, Goto Keiko, Doi Ikuko, Nagata Noriko, Ikeda Yoshiaki, Sakuta Atsushi, Sasaki Nobuya, Ishii Koji
Ibaraki Prefectural Institute of Public Health, Mito, Ibaraki, 310-0852, Japan.
Laboratory of Laboratory Animal Science and Medicine, Faculty of Veterinary Medicine, Kitasato University, Towada, Aomori, Japan.
BMC Vet Res. 2019 Mar 12;15(1):87. doi: 10.1186/s12917-019-1816-x.
Hepatitis E virus (HEV) is prevalent in pigs and may serve as a reservoir for human infection. However, data on HEV infections in pigs in Ibaraki Prefecture, Japan, are limited. Here, we clarified the process and course of HEV in naturally infected pigs. Serum (n = 160) and liver (n = 110) samples were collected from pigs at the slaughterhouse. Furthermore, serum samples were collected from 45 breeding sows and serum and feces samples were collected from 7 piglets once a week (raised until 166 days of age). HEV antigen and antibodies were evaluated, and the genotype was identified based on molecular phylogenetic tree analysis.
The samples collected from the slaughterhouse revealed that few pigs were HEV carriers but most possessed anti-HEV antibodies. Most breeding sows possessed antibodies, and the piglets excreted HEV on the farm at approximately 10 weeks of age. One pig was initially infected, and in a few weeks, the other pigs living in the same sty became infected.
Most pigs in Ibaraki Prefecture were with HEV. On the farm, most piglets were infected with HEV by the time they reached slaughter age. We confirmed that HEV infection is successively transmitted among piglets living in the same sty.
戊型肝炎病毒（HEV）在猪中普遍存在，可能是人类感染的储存宿主。然而，关于日本茨城县猪的戊型肝炎病毒感染的数据有限。在此，我们阐明了自然感染猪中戊型肝炎病毒的感染过程和病程。从屠宰场的猪中采集血清样本（n = 160）和肝脏样本（n = 110）。此外，每周从45头繁殖母猪中采集血清样本，从7头仔猪中采集血清和粪便样本（饲养至166日龄）。对戊型肝炎病毒抗原和抗体进行评估，并基于分子系统发育树分析鉴定基因型。
从屠宰场采集的样本显示，很少有猪是戊型肝炎病毒携带者，但大多数猪具有抗戊型肝炎病毒抗体。大多数繁殖母猪具有抗体，仔猪在农场约10周龄时排出戊型肝炎病毒。最初有一头猪被感染，几周内，生活在同一猪舍的其他猪也被感染。
茨城县的大多数猪感染了戊型肝炎病毒。在农场，大多数仔猪到屠宰年龄时已感染戊型肝炎病毒。我们证实戊型肝炎病毒感染在生活在同一猪舍的仔猪之间相继传播。
