High prevalence of hepatitis E virus infection among domestic pigs in Ibaraki Prefecture, Japan

Abstract

BackgroundHepatitis 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.ResultsThe 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.ConclusionsMost 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.

Evaluation of High-Pressure Processing in Inactivation of the Hepatitis E Virus

“…Multiple lines of evidence indicate that infection with HEV-3 is common among domestic swine in developed countries (reviewed in Salines et al, 2017); however, HEV-3 viremia in swine does not cause any noticeable clinical symptoms (Krog et al, 2019;Motoya et al, 2019). HEV-3 infection of domestic swine can potentially result in contamination of pork products.…”

Nationwide survey of hepatitis E virus infection among wildlife in Japan

“…The prevalence of anti-HEV antibodies in the wild boar population ranged from 4.9% to 57.6% in Europe [1,2,6,11,18,19,43,56,68], and from 4.5% to 38.1% in Asian countries [8,22,46]. In Japan, HEV seropositivity rates among wild boar varied by prefecture, ranging from 4.5% to 42% [13,29,31,46]. In this study, the prefectures of Chiba and Gunma, which are located in the Kanto region showed higher rates of seropositivity in comparison to other regions (Fig.…”

Isolation and Genome Sequencing of Hepatitis E Virus Genotype 1 Imported from India to Japan

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