High Pathogenicity Avian Influenza (HPAI) H5 found in cats on poultry farm in Belgium
25 March 2025
High pathogenicity avian influenza has been detected in two symptomatic cats living on an infected poultry farm in Belgium. A joint press release by the Belgium Federal Agency for the Safety of the Food Chain, Sciensano and the FPS Public Health, Food Chain Safety and the Environment released on 4th March 2025, announced detection of the virus. The cats displayed severe clinical signs and were euthanased. They were likely infected by consuming contaminated eggs or by drinking infected water, although a definite transmission route remains unconfirmed.
In cats, the virus primarily targets the brain and respiratory tract. Resulting clinical signs can include lethargy, dyspnoea, neurological signs (e.g. ataxia, blindness, tremors, seizures and obtundation), or unexpected death. Infection is progressive and attempted treatment mainly supportive.
This is the first case of infected domestic cats in Belgium, although not the first in Europe. The risk to GB pets remains low but the Government has advised that it is important for veterinarians to remain attentive to the disease while maintaining a proportionate response. A map of reported wild bird mortality and findings of avian influenza virus can be found here.
Influenza A (H5N1) is notifiable in mammals. Suspicion of influenza A viruses in mammals must be reported immediately. Guidance on suspect case definition and how to report are available on GOV.UK: Influenza A (H5N1) infection in mammals: suspect case definition and diagnostic testing criteria – GOV.UK (www.gov.uk).
Human infection is possible, although rare, and unprotected exposure to any sick or dead infected animal or contaminated environment increases the risk of infection. Veterinary professionals and support staff should take precautions when handling wild birds, pet birds or cats suspected of or positive for HPAI H5N1 infection.
Further information is available as follows:
Joint press release by the FASFC, Sciensano and the FPS Public Health, Food Chain Safety and Environment | Federal Agency for the Safety of the Food Chain
Wild Bird Reports (arcgis.com)