Infectious Diseases 2022

Infectious Diseases 2022

HPAI (H5N1) virus detected in wild foxes (Vulpes vulpes) in Ontario

5 May, 2022

The Canadian Food Inspection Agency (CFIA) and the Animal Health Laboratory, the CWHC ON/NU diagnosed influenza A (H5N1) in 2 wild fox kits in Ontario, on May 2, 2022. These cases represent the first detections of highly pathogenic avian influenza virus (HPAIV) H5N1 A/goose/Guangdong/1996 (Gs/GD) lineage in wild mammals in Ontario, Canada and in the Americas. One was dead and one had severe neurologic symptoms and died shortly after admission. H5N1 was found in brain tissue samples, and officials said the virus was likely the cause of death. Although these cases represent the first detections of influenza A (H5N1) viruses in wild mammals in Ontario, influenza A (H5N1) virus is known to affect a variety of wild mammals, including wild fox kits in Europe.
Foxes are susceptible to infection with a wild bird isolate of HPAI virus (H5N1) from clade 2.2, can become infected after feeding on infected bird carcasses, and can excrete the virus for as many as 5 days without severe disease developing [Reperant et al. Highly pathogenic avian influenza virus (H5N1) infection in red foxes fed infected bird carcasses. Emerging Infectious Diseases. 2008 Dec;14(12):1835.]