USDA confirms first case of bird flu in Nebraska dairy cattle

Photo: Adene Sanchez/peopleimages.com/Adobe Stock

State and federal officials have confirmed highly pathogenic avian influenza H5N1 (H5N1) in a dairy cattle herd in Nebraska, the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) announced on September 15.¹ The detection marks the first known case of avian influenza in the state.

“APHIS is working closely with the Nebraska Department of Agriculture to conduct additional on-farm investigation, testing, and gathering of additional epidemiological information to better understand this detection and limit further disease spread,” the federal agency wrote in its announcement.¹

Genetic testing by the National Veterinary Services Laboratories (NVSL) revealed the virus belongs to the 2.3.4.4b clade and the B3.13 genotype, which have been associated with the current outbreak of H5N1 in US dairy cows. According to the USDA APHIS, officials were able to detect the virus through state tracing and investigation after H5N1 was found in milk samples collected as part of a pre-movement surveillance required under a federal order issued by the USDA in April 2024.

The federal requirement mandates that lactating dairy cows be tested for H5N1 before being shipped across state lines.² In December 2024, the USDA expanded the order to mandate that raw milk samples nationwide be collected and submitted to the USDA for H5N1 testing.³

Only a small number of H5N1 cases have been detected in livestock this year, although 17 states have experienced bird flu infections since the outbreak started in March 2024.

Related: A veterinarian’s role in bird flu client education

The USDA APHIS said the detection does not affect the safety of the commercial milk supply or pose a risk to consumer health. “The... [FDA] is confident that pasteurization is effective at inactivating H5N1, and that the commercial, pasteurized milk supply is safe,” the USDA APHIS wrote.¹ “Dairies are required to send only milk from healthy animals into processing for human consumption.”

According to the agency, milk from impacted animals is being kept out of the commercial milk tank or destroyed to prevent it from entering the human food supply.

As fall migratory bird season approaches, the USDA APHIS is advising dairy farms to adopt stronger biosecurity measures and immediately report any livestock with clinical signs to their state veterinarian. State veterinarians should also be notified of unusual sick or dead wildlife animals, the agency said.

Clinical signs of H5N1 in dairy cattle include low appetite, decreased milk production, and abnormal appearance of milk, which may be thickened or discolored. According to the American Veterinary Medical Association, the outbreak has impacted lactating cows the most.⁴

The bird flu threat beyond the herd: Felines in the crosshairs

Still, livestock are not the only animals at risk. Domestic cats and wild feline species are especially susceptible to H5N1. Clinical signs of infection in these animals can include fever, lethargy, respiratory distress, anorexia, reddened or inflamed eyes, neurologic signs such as tremors, seizures, incoordination, or blindness, and death.^5,6

“Cats are a really good measure of where bird flu is in the community because they could be serving as sentinels. They could [catch] this virus through hunting outside and eating an infected bird, for instance, or [through] drinking raw milk or eating raw meat,” Deborah Thomson, DVM, founder and executive director of the nonprofit organization One Health Lessons, told dvm360.⁷

Related: Recommendations for veterinarians evaluating feline cases of H5N1

Since December 2024, there have been reports of at least 5 raw cat food products that have been suspected or confirmed to be contaminated with H5N1.^8-11 At least 5 indoor cats have died from exposure to the virus through contaminated raw cat food or raw milk.¹¹ Last year, avian influenza was also identified in 16 wild bobcats in New York state.¹²

“If you suspect that a cat or another patient has H5N1, then it is best to have them in the isolation ward, contact your local public health authority, and ask them what the protocol [is] for that moment. When it comes to bird flu, or any other emerging infectious disease, rules can change quite often, so just stay up to date and contact your local public health authority,” said Thomson.⁷

References

1. USDA confirms highly pathogenic avian influenza in dairy herd in Nebraska. News release. US Department of Agriculture Animal and Plant Health Inspection Service. September 15, 2025. Accessed September 16, 2025. https://www.aphis.usda.gov/news/agency-announcements/usda-confirms-highly-pathogenic-avian-influenza-dairy-herd-nebraska
2. Federal orders. US Department of Agriculture Animal and Plant Health Inspection Service. July 30, 2025. Accessed September 16, 2025. https://www.aphis.usda.gov/livestock-poultry-disease/avian/avian-influenza/hpai-detections/livestock/federal-order
3. Bautista-Alejandre A. Unpasteurized milk will now be tested in effort to tackle H5N1 in dairy cattle. dvm360. January 6, 2025. Accessed September 16, 2025. https://www.dvm360.com/view/unpasteurized-milk-will-now-be-tested-in-effort-to-tackle-h5n1-in-dairy-cattle
4. Avian influenza virus type A (H5N1) in U.S. dairy cattle. American Veterinary Medical Association. September 15, 2025. Accessed September 16, 2025. https://www.avma.org/resources-tools/animal-health-and-welfare/animal-health/avian-influenza/avian-influenza-virus-type-h5n1-us-dairy-cattle
5. Bautista-Alejandre A. FDA releases guidance to prevent bird flu risk in cats. dvm360. December 18, 2024. Accessed September 16, 2025. https://www.dvm360.com/view/fda-releases-guidance-to-prevent-bird-flu-risk-in-cats
6. Bautista-Alejandre A. Recommendations for veterinarians evaluating feline cases of H5N1. dvm360. August 28, 2024. Accessed September 16, 2025. https://www.dvm360.com/view/recommendations-for-veterinarians-evaluating-feline-cases-of-h5n1
7. Thomson D, Bautista-Alejandre A. Cats as H5N1 indicators in the community and response steps. dvm360. August 12, 2025. Accessed September 16, 2025. https://www.dvm360.com/view/cats-as-h5n1-indicators-in-the-community-and-response-steps
8. McCafferty C. Raw cat food tests positive for H5N1. dvm360. September 4, 2025. Accessed September 16, 2025. https://www.dvm360.com/view/raw-cat-food-tests-positive-for-h5n1
9. McCafferty C. Additional cat food company announces recall over H5N1 concerns. dvm360. March 18, 2025. Accessed September 16, 2025. https://www.dvm360.com/view/additional-cat-food-company-announces-recall-over-h5n1-concerns
10. McCafferty C. WSDA and ODA identifies raw pet food as source of bird flu infections. dvm360. February 18, 2025. Accessed September 16, 2025. https://www.dvm360.com/view/wsda-and-oda-identifies-raw-pet-food-as-source-of-bird-flu-infections
11. Bautista-Alejandre A. Several cat deaths reported following bird flu exposure through raw pet food and milk. dvm360. January 16, 2025. Accessed September 16, 2025. https://www.dvm360.com/view/several-cat-deaths-reported-following-bird-flu-exposure-through-raw-pet-food-and-milk
12. Coppock Crossley K. Researchers find avian influenza in New York bobcats. dvm360. April 3, 2025. Accessed September 16, 2025. https://www.dvm360.com/view/researchers-find-avian-influenza-in-new-york-bobcats