Farms in the county test positive for H5N1 – Welcome to San Bernardino County

H5N1 has been detected in four dairy farms in San Bernardino County.

H5N1 – bird flu – has been detected in four dairy farms in San Bernardino County. The risk of infection from H5N1 remains relatively low. No person-to-person spread of bird flu has been detected in California.

“While the risk of bird flu to the general public remains low, the detection of this virus in animals across multiple farms serves as a reminder to practice caution when handling animals or animal products,” said San Bernardino County Health Officer Sharon Wang. “It’s crucial to avoid raw milk consumption and follow proper food safety practices to reduce any potential risk of exposure.”

Symptoms of H5N1 in humans

Symptoms typically appear within two to eight days of exposure, but can be up to 10 days, and may include:

Eye redness or discharge
Cough or sore throat
Runny or stuffy nose
Diarrhea or vomiting
Muscle or body aches
Headaches
Fatigue
Difficulty breathing
Fever

Preventive measures for residents and pets

Avoid consuming unpasteurized “raw” milk and undercooked meat. Raw milk can contain harmful germs that may cause serious illness, particularly in children under 5 years old, pregnant individuals, and people with weakened immune systems. Choose pasteurized milk and dairy products, as the pasteurization process eliminates the bird flu virus.
Individuals who interact with infected dairy cows, poultry or wildlife are at greater risk of infection.
Wear protective clothing when working with birds, wildlife, livestock or their environments.
Refrain from working with sick animals or those exposed to avian influenza.
Wash hands frequently after handling animals or being in their environment.

Stay healthy

As respiratory illnesses become more prevalent, residents are encouraged to:

Stay up to date on vaccines for influenza, COVID-19 and RSV, particularly those at high risk, including pregnant individuals, to help protect babies who are born too young to be vaccinated. While these vaccines will not protect against bird flu, getting vaccinated can lower the risk of being infected with multiple infections at the same time.
Practice good hand hygiene.
Wear a mask in crowded or high-risk settings.

For more details on bird flu, please visit the California Department of Public Health’s Current Bird Flu Situation webpage. If you have any further questions, please contact the San Bernardino County Department of Public Health’s Communicable Disease Section at 1-800-722-4794, Monday through Friday, 8 a.m. – 5 p.m., or 1-800-472-2376 after-hours, including weekends and holidays.

Additional County Update News – March 6, 2025