Virological, pathological, and glycovirological investigations of an Ezo red fox and a tanuki naturally infected with H5N1 high pathogenicity avian influenza viruses in Hokkaido, Japan

• Published in: Virology (New York, N.Y.) N.Y.), 2023-01, Vol.578, p.35-44
• Main Authors: Hiono, Takahiro, Kobayashi, Daiki, Kobayashi, Atsushi, Suzuki, Tamami, Satake, Yuki, Harada, Rio, Matsuno, Keita, Sashika, Mariko, Ban, Hinako, Kobayashi, Maya, Takaya, Fumihito, Fujita, Hiroko, Isoda, Norikazu, Kimura, Takashi, Sakoda, Yoshihiro
• Format: Article
• Language: English
• Subjects: Animals; Ezo red fox; Foxes; High pathogenicity avian influenza virus; Histopathology; Influenza A virus - genetics; Influenza A Virus, H5N1 Subtype; Influenza in Birds - epidemiology; Japan - epidemiology; Receptor; Tanuki; Virulence
• ISSN: 0042-6822; 1096-0341
• DOI: 10.1016/j.virol.2022.11.008

In winter/spring 2021–2022, high pathogenicity avian influenza viruses (HPAIVs) that are genetically closely related to each other were detected worldwide. In a public garden in Sapporo, Hokkaido, Japan, a crow die-off by HPAIV infection occurred from March 29 to May 18, 2022. During the event, H5N1 HPAIVs were isolated from an Ezo red fox (Vulpes vulpes schrencki) and a tanuki (Nyctereutes procyonoides albus) found in the same garden. The fox showed viral meningoencephalitis and moderate virus replication in the upper respiratory tract, whereas the tanuki showed viral conjunctivitis and secondary bacterial infection in the eyes accompanied with visceral larva migrans. Viruses isolated from the fox and the tanuki were genetically closely related to those isolated from crows in the same garden. Various α2-3 sialosides were found in the respiratory tracts of these canid mammals, consistent with HPAIV infections in these animals. This study highlighted the importance of monitoring HPAIV infections in wild carnivore mammals to detect the potential virus spreading in nature. •H5N1 HPAIVs were isolated from an Ezo red fox and a tanuki in Hokkaido, Japan.•These viruses were genetically close to the isolates from crows in the same garden.•The fox showed viral meningoencephalitis with virus growth in the upper airway.•The tanuki showed viral conjunctivitis with the secondary bacterial infection.•The fox and the tanuki had various α2-3 sialosides in their respiratory tracts.