Avian flu detected in Colorado dairy facility for first time in more than 2 years

Highly Pathogenic Avian Influenza (HPAI) has been detected in a dairy in Weld County, the first detection in more than two years.

According to the Colorado Department of Agriculture, risk to the general public remains low and pasteurized milk continues to be safe.

Since 2024, when Colorado became the epicenter of a bird flu outbreak in the United States, state agriculture officials mandated weekly testing of milk samples for bird flu at all commercial dairy farms in the state. The move was the first of its kind in the United States.

Watch below: Past coverage of the bird flu outbreak

This detection underscores the importance of our routine bulk milk tank testing to keep our herds healthy and our food supply secure, Colorado State Veterinarian Dr. Maggie Baldwin. Colorado has taken a proactive approach to monitoring and responding to avian influenza, ensuring that early detection leads to swift mitigation measures to protect consumers and our food supply.

The Colorado State Veterinarian's Office was notified by the Colorado State University Veterinary Diagnostic Laboratory that a sample tested presumptive positive for HPAI, and the National Veterinary Services Laboratory (NVSL) issued the official confirmation of the detection of HPAI (B3.13 strain) in a dairy in Weld County on Oct. 24, according to the state agriculture department.

Because of the quarantine order, there are mandatory stipulations in effect to prevent further transmission of the virus. That includes restricting the movement of lactating dairy cattle from the affected facility, and the dairy must implement strict biosecurity protocols across all farm activity.

Weekly bulk milk tank testing will be required until two consecutive negative tests are obtained at least one week apart.

CDA is working with the Colorado Department of Public Health and Environment to protect farmworkers and facility staff. Officials will monitor people following potential exposure to infected animals as a precaution.

According to CDA, people most at risk for avian flu are those who come into direct contact with infected birds or other animals.

During the 2024 outbreak, Colorado had its first confirmed case in April and it eventually grew to affect 64 individual dairies across the state. CDA said that because of the monitoring effort, all affected dairies were released from quarantine by December 2024.