The U.S. Department of Agriculture’s (USDA) National Veterinary Services Laboratory (NVSL) confirmed a detection of Highly Pathogenic Avian Influenza (HPAI) H5N1 in dairy cows in Northeast Colorado on April 25, 2024. USDA has also confirmed detections in premises in multiple states.
Clinical signs in dairy cattle include a decrease in feed consumption with a simultaneous decrease in rumination and rumen motility; respiratory signs including clear nasal discharge; and subsequent acute drop in milk production. Additional clinical signs may include abnormal tacky or loose feces, lethargy, dehydration, and fever. Severely affected cattle may have thicker, concentrated, colostrum-like milk or produce no milk at all.
For more information about infections in livestock and for additional resources, please visit the USDA website.
Statewide Mandatory Bulk-Tank HPAI Testing
As of the effective date of this Order, all CDPHE-licensed dairy cow farms in the state of Colorado must submit weekly bulk-tank samples for testing as set forth below. This Order does not include raw milk dairies. Raw milk dairies are encouraged to participate in the voluntary bulk tank surveillance program.
Free PPE for ag workers
The Colorado Department of Public Health and Environment is providing up to four weeks of free Personal Protective Equipment to any poultry or dairy farm in Colorado. Submit your request through the form below.
USDA Support for Producers
To help producers enhance their biosecurity practices, USDA is offering additional support for producers who have HPAI confirmed positive dairy herds so they have tools to eliminate the virus and can protect their animals, themselves, their families, and their employees.
Dairy producers with premises that have been confirmed positive for HPAI are eligible for USDA support to conduct activities that best fit their operations.
Producers will work with USDA personnel to develop a plan for their premises—detailing planned testing and movement, biosecurity practices and other planned activities.
Learn more about USDA's Support for Producers with Affected Dairy Premises.
The USDA can help producers with:
- PPE and/or laundering
- Biosecurity planning and implementation
- Heat treatment for waste milk
- Veterinarian costs
- Shipping costs for samples
Information for consumers
USDA and FDA have stated that because commercial milk products are pasteurized before entering the market, at this time there is no concern about the safety of the commercial milk supply.
Pasteurized milk does not pose a risk to consumer health. Pasteurization has continuously proven to inactivate bacteria and viruses in milk.
Despite the detection of HPAI in dairy cattle, the risk to the general public remains low, per CDC. More information is available on CDC’s website regarding the H5N1 Bird Flu Current Situation.
Information for veterinarians
Colorado veterinarians must report cattle illness that presents clinical signs of HPAI 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.
Colorado Cases of HPAI in Dairy Cattle
Information for producers
Biosecurity resources for livestock owners
The Secure Milk Supply website offers comprehensive materials on dairy biosecurity practices, including posters and information sheets in English and Spanish.
Additional biosecurity resources can be found at the following links:
- Biosecurity - National Dairy FARM Program
- Biosecurity Practices for Dairy Operations (Texas A&M University)
- Biosecurity for cattle operations (University of Minnesota Extension)
- Farm Biosecurity - CFSPH (Iowa State University - Center for Food Security and Public Health)
- 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)
- Order free H5N1 PPE (Personal Protective Equipment) for employees
USDA Federal Order
Federal Order
In order to continue to monitor and understand the extent of this virus and reduce the risk of further disseminating HPAI H5N1 virus, resulting in greater threats to poultry and livestock, the USDA issued a Federal Order requiring the following measures, effective Monday, April 29, 2024.
Additionally, the APHIS Requirements and Guidance for the Federal Order help clarify the USDA requirements.
The Colorado State Veterinarian's Office put together a brief memo on the Federal Order.
Pre-movement Testing
Sample Collection and Submission Protocol for Non-Clinical Lactating Dairy Cattle
Who: Accredited Veterinarian, Licensed Veterinarian, or sample collector approved by State Veterinarian (in process)
When: Collected within 7 days of movement
Number: if moving groups of animals: 30 or fewer - all animals must be tested; if more than 30 - only test 30
Samples: milk from individual cows - pool milk from each quarter into one sample - 3-10 ml total per animal (do not pool animals together)
Submit to: NAHLN lab - CSU Veterinary Diagnostic Laboratory. Fort Collins lab is conducting testing; branch labs will forward samples.
Results: Include lactation status and test results on CVI