Bird Flu Alert: Avian Influenza Detected in Montana

October 12, 2023

Helena, Mont. –  On Tuesday, October 10, the Montana Department of Livestock (MDOL) confirmed Highly Pathogenic Avian Influenza (HPAI) in a Glacier County poultry flock. This is Montana’s 18th affected flock linked to the ongoing national HPAI outbreak which began in early 2022. The Department is also awaiting confirmation of a backyard flock in Flathead County. The last confirmed HPAI infection in Montana was April 2023.  

This HPAI variant is spread from migratory waterfowl and infections in domestic poultry follow the spring and fall migrations. This pattern is consistent with detections in South Dakota, Idaho, and New Jersey, as well as Canada and several other countries, in the last 30 days as the fall migration is underway. In early September, in anticipation of an increased risk of exposure associated with the fall migration, MDOL reinstated guidance for poultry owners to house birds indoors to the extent possible and to avoid exposure to wild birds. Domestic poultry become infected through direct contact with infected wild birds, or through contact with contaminated objects, equipment, or the environment. This directive will remain in place until May 2024 pending the HPAI situation at that time.  

Avian influenza is an infectious viral disease of birds that can cause high mortality rates 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, the most consistent presentation has been sudden death of multiple birds within a flock. Samples from flocks with increased mortalities or unusual symptoms are submitted to the Montana Veterinary Diagnostic Laboratory (MVDL) and tested for the presence of avian influenza.

Infected flocks are placed under quarantine until the Department is sure that the premises is free of virus either through cleaning and disinfection or time. Flock owners whose birds are depopulated as part of the process are eligible to receive indemnity from the United States Department of Agriculture (USDA). Depopulation of the Glacier County flock is underway. In addition to restrictions on the affected flock, the Department will conduct disease surveillance of poultry premises within 20 km of the affected premises. Surveillance includes contact with premises to inquire about any sick birds and weekly sampling for premises that may sell poultry or poultry products.

The Department encourages all poultry producers to maintain strong biosecurity and immediately report sudden onset of illness or high death loss in domestic poultry to their veterinarian or the Department at (406/444-2976). If you find sick or dead wild birds that have died from unknown causes, please contact your local FWP Warden, Biologist or Regional office, or call the FWP wildlife veterinarian (406/577-7880).

While HPAI is considered a potentially zoonotic disease, CDC continues to consider the risk to people from wild birds, backyard flocks, and commercial poultry to be low. Public health recommends wearing gloves when handling dead poultry or wild birds and washing hands thoroughly after any contact with birds.

Existing safeguards to keep food safe and wholesome 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 US Department of Agriculture recommends cooking poultry to 165 degrees Fahrenheit.

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 on the Montana Department of Livestock, visit


For more information on biosecurity, please visit the USDA website at

For more information on national cases of HPAI, please visit the USDA website at

For information on human health concerns and HPAI, please visit the CDC website at

Source: MTDOL