H5N1 signals widen with Washington cat death, Dutch cow finding

H5N1 is still turning up in places veterinarians would rather not see it. In late January 2026, Dutch authorities reported antibodies to avian influenza A(H5N1) in milk from a dairy cow in Friesland after a farm cat had tested positive in December 2025, making it the first such detection in cattle in the EU/EEA and the first reported outside the U.S. Testing found no active virus in milk from the sampled cows, and all cattle tested negative on follow-up PCR, suggesting prior exposure rather than ongoing transmission. Separately, Washington state reported a fatal H5N1 infection in an outdoor domestic cat, another reminder that feline spillover continues as the virus circulates in birds and other mammals. (ecdc.europa.eu)

Why it matters: For veterinary professionals, these updates reinforce two practical points: cats remain a sensitive spillover species, and dairy-associated H5N1 surveillance now matters outside North America, too. A recent systematic review found feline H5N1 infections are increasing, with case reports showing roughly 74% mortality and frequent neurologic and respiratory signs. That means veterinarians should keep H5N1 on the differential list for cats with acute respiratory or neurologic disease, especially outdoor cats and those with possible exposure to wild birds, raw poultry, raw pet food, or unpasteurized milk. The Dutch finding also widens the geographic lens for cattle surveillance, even though ECDC says there is currently no sign of active circulation on that farm and its human risk assessment remains unchanged. (pubmed.ncbi.nlm.nih.gov)

What to watch: Watch for the pending Dutch serology results from the rest of the herd, any additional cattle detections in Europe, and whether public health or veterinary agencies issue updated guidance on feline testing and farm biosecurity. (ecdc.europa.eu)