The Japanese Society of Veterinary Science Acta Medica Okayama 0916-7250 81 8 2019 Risk assessment for hepatitis E virus infection from domestic pigs introduced into an experimental animal facility in a medical school 1191 1196 EN Hirohito Ogawa Department of Virology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Haruko Hirayama Department of Animal Resources, Advanced Science Research Center, Okayama University Satsuki Tanaka Department of Virology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Norio Yata Department of Animal Resources, Advanced Science Research Center, Okayama University Hikaru Namba Department of Virology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nobuko Yamashita Department of Virology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kenzo Yonemitsu Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University Ken Maeda Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University Katsumi Mominoki Department of Animal Resources, Advanced Science Research Center, Okayama University Masao Yamada Department of Virology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Hepatitis E virus (HEV) is known to cause zoonotic infections from pigs, wild boars and deer. Domestic pigs have been used as an experimental animal model in medical research and training; however, the risks of HEV infection from pigs during animal experiments are largely unknown. Here, we retrospectively investigated the seroprevalence and detection rates of viral RNA in 73 domestic pigs (average 34.5 kg) introduced into an animal experimental facility in a medical school during 2012-2016. We detected anti-HEV immunoglobulin G antibodies in 24 of 73 plasma samples (32.9%), though none of the samples were positive for viral RNA. Plasma samples of 18 pigs were sequentially monitored and were classified into four patterns: sustained positive (5 pigs), sustained negative (5 pigs), conversion to positive (6 pigs) and conversion to negative (2 pigs). HEV genomes were detected in 2 of 4 liver samples from pigs that were transported from the same farm during 2016-2017. Two viral sequences of the overlapping open reading frame (ORF) 2/3 region (97 bp) were identical and phylogenetically fell into genotype 3. A 459-bp length of the ORF2 region of an amplified fragment from a pig transported in 2017 was clustered with the wbJYG1 isolate (subgenotype 3b) with 91.5% (420/459 bp) nucleotide identity. Based on our results, we suggest that domestic pigs introduced into animal facilities carry a potential risk of HEV infection to researchers, trainees and facility staff. Continuous surveillance and precautions are important to prevent HEV infection in animal facilities. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1999-4915 9 12 2017 Characterization of a Novel Bat Adenovirus Isolated from Straw-Colored Fruit Bat (Eidolon helvum). 371 EN Hirohito Ogawa Department of Virology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiro Kajihara Division of Global Epidemiology, Research Center for Zoonosis Control, Hokkaido University Naganori Nao Division of Global Epidemiology, Research Center for Zoonosis Control, Hokkaido University Asako Shigeno Division of Global Epidemiology, Research Center for Zoonosis Control, Hokkaido University Daisuke Fujikura Division of Infection and Immunity, Research Center for Zoonosis Control, Hokkaido University Bernard M. Hangfombe Department of Paraclinical Studies, School of Veterinary Medicine, University of Zambia Aaron S. Mweene Department of Disease Control, School of Veterinary Medicine, University of Zambia Alisheke Mutemwa Provincial Veterinary Office, Department of Veterinary Services, Ministry of Fisheries and Livestock David Squarre Department of National Parks and Wildlife, Ministry of Tourism and Arts Masao Yamada Department of Virology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hideaki Higashi Division of Infection and Immunity, Research Center for Zoonosis Control, Hokkaido University Hirofumi Sawa Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University Ayato Takada Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University Bats are important reservoirs for emerging zoonotic viruses. For extensive surveys of potential pathogens in straw-colored fruit bats (Eidolon helvum) in Zambia, a total of 107 spleen samples of E. helvum in 2006 were inoculated onto Vero E6 cells. The cell culture inoculated with one of the samples (ZFB06-106) exhibited remarkable cytopathic changes. Based on the ultrastructural property in negative staining and cross-reactivity in immunofluorescence assays, the virus was suspected to be an adenovirus, and tentatively named E. helvum adenovirus 06-106 (EhAdV 06-106). Analysis of the full-length genome of 30,134 bp, determined by next-generation sequencing, showed the presence of 28 open reading frames. Phylogenetic analyses confirmed that EhAdV 06-106 represented a novel bat adenovirus species in the genus Mastadenovirus. The virus shared similar characteristics of low G + C contents with recently isolated members of species Bat mastadenoviruses E, F and G, from which EhAdV 06-106 diverged by more than 15% based on the distance matrix analysis of DNA polymerase amino acid sequences. According to the taxonomic criteria, we propose the tentative new species name "Bat mastadenovirus H". Because EhAdV 06-106 exhibited a wide in vitro cell tropism, the virus might have a potential risk as an emerging virus through cross-species transmission. No potential conflict of interest relevant to this article was reported.