H5N1 updates put cats and dairy surveillance back in focus

A new set of H5N1 updates is sharpening attention on cats as both victims and sentinels of spillover. In Washington state, an outdoor domestic cat in Grant County tested positive for H5N1 after what officials suspect was exposure to wild birds; state surveillance documents list the case as detected on January 20, 2026. In the Netherlands, follow-up testing on a Friesland dairy farm where a cat had already tested positive found H5N1 antibodies in one cow, and later in five cows total, indicating prior exposure rather than active infection. Dutch investigators reported no viral RNA in blood or milk samples, and Wageningen University said the original cow had mastitis and reduced milk yield in mid-December before recovering. (wormsandgermsblog.com)

Why it matters: For veterinary professionals, these cases reinforce two practical points: outdoor access and raw animal products remain important feline exposure routes, and unexplained illness or death in cats may be an early warning sign for H5N1 on mixed-species farms. Washington guidance for companion animal veterinarians says the general-population risk in cats is low, but flags raw milk and raw pet food as known exposure risks, while Dutch and UK assessments suggest the Netherlands cattle finding does not yet indicate broader circulation or active shedding in European dairy herds. (cms.agr.wa.gov)

What to watch: Watch for any additional cattle positives, sequence data, or evidence of onward transmission in Europe, and for more formal guidance on feline surveillance tied to wild bird exposure and raw diets. (assets.publishing.service.gov.uk)