Authorities are imposing containment measures as governments monitor risks to food supply and public health.
H5N1 is a subtype of the influenza A virus that primarily causes avian influenza in birds, but it can also infect mammals.
H5N1 infections in cats have been reported in other countries globally, often linked to consuming infected birds, raw meat, or contaminated farm products.
The organization urged members to share genetic sequences of avian influenza viruses in public databases and to employ scientifically justified import measures rather than blanket trade bans.
The World Organisation for Animal Health (WOAH) confirmed that Belgium and Slovakia became the latest countries to report cases this week.
The case underscores how avian flu remains a persistent threat to animal health and trade stability.
Argentina had previously declared itself free of H5N1 in August 2023 following a successful stamping-out and surveillance campaign.
With migratory birds clustering in Europe during winter months, proactive biosecurity is essential to prevent infections from entering farms.
The research announcement coincided with confirmation of a major new HPAI H5N1 outbreak in Jefferson County, Wisconsin involving more than 3 million birds.
The discussions coincide with Brazil being selected by FAO to host an international meeting on bird flu prevention and control later this year.