2022/2023/2024 HPAI Outbreak
Since March 2022, the Colorado Department of Agriculture has led a response to the outbreak of Highly Pathogenic Avian Influenza (HPAI).
HPAI continues to pose a threat to Colorado's domestic birds. Bird owners should maintain biosecurity measures such as keeping their flocks away from wild birds and not touching any dead wild birds.
Domestic bird owners should take extra precautions to avoid introducing the HPAI virus to their flocks, including:
- preventing interaction between domestic and wild birds,
- keeping food and water sources away from migrating birds,
- and monitoring flocks for signs of illness or death.
Do you have sick or dead domestic poultry?
Veterinarians and backyard, hobby, and commercial producers should report any suspicious disease events in poultry flocks to the State Veterinarian’s using this form.
Situation Reports
New situation reports will be posted here on Fridays, if new information is available.
View all situation reports here (2022-2024)
HPAI in Dairy Cattle
Information for producers
The U.S. Dept. of Agriculture’s APHIS reported on March 25, 2024 that milk and other samples from sick cattle collected from two dairy farms in Kansas and two in Texas have tested positive for highly pathogenic avian influenza.
To date, no cases have been identified in Colorado and the State Veterinarian’s office continues to monitor the situation.
There is no threat to human health: commercial milk supply remains safe due to both federal animal health requirements and pasteurization, which kills influenza viruses.
Wild migratory birds are the source of infection and viral testing and an investigation is ongoing. There have been no reports of similar clinical symptoms in beef herds in any of the affected areas.
Symptoms in dairy cows include low appetite, decreased milk production and abnormal colostrum-like milk.
What can cattle owners do?
- Dairy cattle and other livestock owners whose animals are showing symptoms should contact their herd veterinarians.
- Producers are encouraged to practice good biosecurity when coming or going from their farm and when traveling between farms. You can learn more about wild bird biosecurity on our HPAI landing page.
- Producers should consider pasteurization of all milk products being fed to calves.
- Because this virus is spread by wild birds, limiting interaction with birds and wild bird feces may reduce risk of exposure.
For more information, please read the USDA press release about the detections or the press release from the Texas Animal Health Commission.
Additional resources for livestock owners
Please note that some of these resources are from external sources and do not meet accessibility requirements.
The links below take you to content CDA does not control. Please contact us at cda_a11y@state.co.us if you’d like assistance with this content.
- Information on HPAI Detections in Livestock from USDA - APHIS
- Dairy Biosecurity Recommendations – HPAI and More (American Association of Bovine Practitioners)
- Influenza A in Bovine Species: A Narrative Literature Review (National Library of Medicine)
The Secure Milk Supply website offers comprehensive materials on dairy biosecurity practices, including posters and information sheets in English and Spanish.
Information for veterinarians
Colorado veterinarians should report cattle illnesses to the State Veterinarian’s office at (303)-869-9130, via the Reportable Disease Case Report Form, or to their local Veterinary Medical Officer.
Reportable Disease Case Report Form
Veterinarians can request HPAI testing for samples that meet the criteria.
Please contact the State Veterinarian’s office to receive guidance for sample collection and how to submit your sample. Samples will not be processed without contacting us first.
Contact us at 303-869-9130 or animalhealth@state.co.us.
Premovement Testing Information
If cattle must be moved, APHIS recommends premovement testing of milk samples from lactating cows and nasal swabs for non-lactating cattle, by PCR for Influenza A and H5 virus, at a NAHLN laboratory for individual animals (statistical sample of lots). It should be noted that how the virus is infecting dairy cattle, the duration, and route of H5N1 virus shedding is not yet known; a negative result does not guarantee the animal is free of H5N1.
Premovement testing information can be found by contacting the Colorado State University Veterinary Diagnostic Laboratory or by calling (970) 297-1281.
Wild bird mortalities
HPAI is actively circulating in wild birds across Colorado. Wild birds may be infected with avian influenza without showing symptoms. Learn more about HPAI and wild birds from Colorado Parks and Wildlife.
Coloradans are asked not to touch any dead birds they find on public lands and not to walk on ice to retrieve any carcasses. Do not handle any dead or dying birds.
Colorado Parks and Wildlife is aware of and tracking multiple wild bird mortalities. If you find three or more dead wild birds in a specific area within a two week period, you may notify your local CPW office.
For individual carcasses found on private property, if necessary, members of the public may wear a mask and gloves to pick up a carcass, immediately double bag it, and place the bags in municipal trash. Discard gloves and mask and wash your hands immediately afterwards.
Mammalian detections
There are many species of animals potentially susceptible to HPAI. In addition to birds and poultry, H5N1 viruses have been detected in some mammals. Infection may cause illness, including severe disease and death in some cases. The USDA is tracking mammalian detections on the national level.
In Colorado, CDA is coordinating the response to detections in wild animals with the Department of Natural Resources and Colorado Parks and Wildlife. You can see the Colorado detections in the map and spreadsheet below.
Companion animals
Although the risk is lower than it is to birds and cases are rare, domestic animals (e.g., cats or dogs) could become infected with avian flu if they go outside and eat or are exposed to sick or dead birds infected with avian flu viruses, or an environment contaminated with feces of infected birds.
People should avoid contact between their pets and wild birds or areas contaminated with avian flu virus. I
If you suspect your pet may have been exposed to HPAI, and is showing symptoms of illness, contact your veterinarian and monitor yourself for symptoms.
Human Detections
There have been rare cases of human infection with avian influenza. More information can be found at the CDC website.
Color coding legend for HPAI map
Click on each county for full details.
