Komami Minami, Komu James G, Ishiguro Yuki, Sasaki Motoki, Matsuda Sachiko, Jamsransuren Dulamjav, Bui Vuong Nghia, Watanabe Yohei, Imai Kunitoshi, Ogawa Haruko, Takeda Yohei
Department of Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
Graduate School of Animal and Veterinary Sciences and Agriculture, Obihiro University of Agriculture and Veterinary Medicine, 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan; Department of Medical Laboratory Sciences, College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya.
Virus Res. 2025 Jan;351:199515. doi: 10.1016/j.virusres.2024.199515. Epub 2024 Dec 24.
In recent years, infection cases of H5 subtype highly pathogenic avian influenza viruses (HPAIVs) in wild mammals have increased globally. To obtain recent epidemiological information regarding influenza A virus (IAV) infection in raccoons (Procyon lotor), the prevalence of anti-IAV antibodies in sera was analyzed among raccoons captured in Tokachi District, Hokkaido, Japan, from 2019 to 2023. Screening of serum samples using enzyme-linked immunosorbent assay and agar gel precipitation test detected anti-IAV antibodies in 5 of 114 (4.4 %) raccoons. All positive sera were from raccoons captured from 2022 to 2023. The hemagglutination inhibition test revealed that all five serum samples contained anti-H5 subtype HPAIV antibodies, and one also contained anti-H1 subtype antibodies. The neuraminidase inhibition test revealed that all five sera contained anti-N1 subtype antibodies, and one also contained anti-N8 subtype antibodies. In the virus neutralization test, these five sera showed stronger neutralization activity against the H5 subtype clade 2.3.4.4b HPAIV strain recently circulating worldwide compared to the old H5 HPAIV strain isolated in Japan in 2007. These findings suggested that raccoons could be involved in the circulation of H5 HPAIVs in nature.
近年来，野生哺乳动物中H5亚型高致病性禽流感病毒（HPAIV）的感染病例在全球范围内有所增加。为了获取有关浣熊（Procyon lotor）感染甲型流感病毒（IAV）的最新流行病学信息，对2019年至2023年在日本北海道十胜地区捕获的浣熊血清中抗IAV抗体的流行情况进行了分析。使用酶联免疫吸附测定和琼脂凝胶沉淀试验对血清样本进行筛查，在114只浣熊中有5只（4.4%）检测到抗IAV抗体。所有阳性血清均来自2022年至2023年捕获的浣熊。血凝抑制试验显示，所有五份血清样本均含有抗H5亚型HPAIV抗体，其中一份还含有抗H1亚型抗体。神经氨酸酶抑制试验显示，所有五份血清均含有抗N1亚型抗体，其中一份还含有抗N8亚型抗体。在病毒中和试验中，与2007年在日本分离的旧H5 HPAIV毒株相比，这五份血清对最近在全球流行的H5亚型2.3.4.4b分支HPAIV毒株表现出更强的中和活性。这些发现表明，浣熊可能参与了H5 HPAIVs在自然界中的传播。
