The Montana Department of Livestock confirmed highly pathogenic avian influenza on 17 September in Ravalli County, in a small commercial flock of chickens — the second detection in the state this year, after a flock found in January 2026.

Migratory waterfowl are the main source of the virus, with the highest risk in spring and autumn migration; domestic poultry are infected through contact with wild birds or with contaminated equipment and surroundings, and cases have appeared year-round across the country. Other species exposed to large amounts of virus can be infected too, most often cats and small carnivores such as skunks and raccoons.

The department recommends keeping birds indoors where possible, practising good biosecurity and watching flocks once or twice a day: sudden death is the commonest sign, but owners may also see sneezing, coughing, discoloured combs, swollen eyes and lethargy. 'While only a small number of Montana flocks have been impacted, the risk to poultry is increased during wild bird migration,' said Dr Emily Kalecyzc, assistant state veterinarian. 'Whether you have a large commercial poultry operation or a small backyard flock, ongoing vigilance and increased biosecurity remains important.'

The Centers for Disease Control considers the risk to the general public low, though people in contact with infected animals or contaminated objects are at higher risk; officials advise gloves when handling sick or dead birds and thorough hand-washing. HPAI is not a food-safety concern, and USDA recommends cooking poultry to at least 165°F.

Producers are asked to report sudden illness or high death loss at once to their veterinarian or the department, and to report sick or dead wild birds to Fish, Wildlife and Parks; the department's mandate is to control and eradicate animal disease, prevent its spread to people and protect the livestock industry.

Source: Northern Ag Network