On Wednesday, September 10, the Montana Department of Livestock (MDOL) confirmed Highly Pathogenic Avian Influenza (HPAI) in north central Montana, the state’s first detection in domestic poultry this fall. Montana has confirmed 31 affected flocks linked to the ongoing national outbreak which began in 2022. The most recent previous detection was in Gallatin County in March.
Migratory waterfowl are the primary source of the virus and infections in domestic poultry are often associated with spring and fall migrations. Domestic poultry may become infected through direct contact with infected wild birds, or through contact with contaminated objects, equipment, or the environment. MDOL recommends poultry owners house birds indoors to the extent possible and use good biosecurity practices to minimize disease risk through the fall migration. Premises with multiple species should also consider precautions to prevent diseases moving between species in addition to limiting contact with wild birds.
HPAI is a potentially zoonotic disease with 70 human cases reported nationally. The Centers for Disease Control (CDC) continues to consider the risk to the general population from this virus to be low, however, the risk is moderate to high for individuals in contact with potentially infected animals or contaminated environments. Public health officials recommend wearing gloves when handling sick or dead birds and washing hands thoroughly after contact with poultry.
HPAI has also been confirmed in multiple other species associated with this outbreak, most notably in dairy cattle. MDOL has worked closely with Montana’s dairy industry to conduct monthly surveillance since December of 2024 with no detections of HPAI in milk samples.
“With the increased risk to people working around infected animals and viral spread to other species, we cannot stress enough the importance of preventive measures,” said Tahnee Szymanski, State Veterinarian. “The next critical piece is rapid reporting of sick and dead animals to limit disease spread.”
Avian influenza is an infectious viral disease of birds that can cause high death loss in domestic flocks. Sick birds can exhibit numerous signs such as swollen eyes, discolored comb and legs, or a significant drop in egg production or water and feed consumption. However, clinical signs are rarely reported with poultry owners primarily noting the sudden death of multiple birds within a flock.
HPAI is not a food safety concern. Existing safeguards to keep food, safe and wholesome, including the pasteurization of milk, are sufficient to protect people, and the food supply in the United States is one of the safest in the world. As a reminder, the United States Department of Agriculture (USDA) recommends cooking poultry to 165 degrees Fahrenheit.
The Department encourages all poultry producers to immediately report sudden onset of illness or high death loss in domestic poultry to their veterinarian or MDOL at (406/444-2976). If you find sick or dead wild birds that have died from unknown causes, please contact your local Fish, Wildlife, and Parks Warden, Biologist or Regional office, or call the FWP wildlife veterinarian (406/577-7880). Additionally, dairy producers who observe a sudden decrease in milk production, decreased appetite, fever, respiratory disease or loose feces that cannot be otherwise explained are encouraged to report to their veterinarian or MDOL. Raw milk from sick cows should not be consumed.
The mission of the Montana Department of Livestock is to control and eradicate animal diseases, prevent the transmission of animal diseases to humans, and to protect the livestock industry from theft and predatory animals. For more information, visit www.liv.mt.gov.
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Montana Department of Agriculture
