For nearly 30 years, the H5N1 strain of highly pathogenic avian influenza (HPAI) has been a looming threat to poultry producers worldwide. In recent years, however, the virus has evolved in concerning ways—expanding its host range, appearing in unexpected places, and raising alarms among scientists and public health officials.

Why H5N1 Matters for Poultry Producers
There are numerous poultry conditions and diseases that growers are concerned with and manage their flocks to avoid. H5N1 is becoming more concerning because when it enters a flock of domestic poultry—whether chickens, turkeys, ducks, or gamebirds—it spreads quickly and can kill large numbers of birds before symptoms even appear. Clinical signs may include diarrhea, nasal discharge, coughing, sneezing, or loss of coordination, but sudden death without warning is common. Not surprisingly, once H5N1 is detected on a farm, federal and state protocols require the rapid depopulation of the farm to contain the disease, and affected states face restrictions on poultry exports.

Given the seriousness of H5N1, we know that, for producers, the stakes are clear: outbreaks disrupt supply chains, devastate flocks, and can cause long-lasting financial and reputational damage.

A Changing Virus With New Risks
Traditionally associated with wild waterfowl, the H5N1 virus has recently been confirmed in dozens of mammal species—including foxes, skunks, raccoons, sea lions, and even cattle. In 2025, viral genetic material was detected in approximately one in five milk samples tested, although no live virus was found in pasteurized dairy products. This unusual spillover highlights the adaptability of H5N1 and underscores the importance of poultry operations remaining vigilant.

As the virus evolves, the most significant concern is that H5N1 may adapt to spread efficiently among mammals—particularly pigs, which serve as “mixing vessels” for human and avian influenza viruses. From swine, it could acquire the ability to spread between people.

Impacts on Human Health
Since 1996, nearly 900 human infections with H5N1 have been reported worldwide, with a case fatality rate of more than 50%. In the U.S., there has been one recent suspected case of transmission from a dairy cow to a worker. While symptoms were mild, experts continue to caution that further surveillance is necessary

Currently, there is no evidence of sustained human-to-human transmission. Antiviral treatments, such as Tamiflu, appear to remain effective, and vaccine platforms exist should an H5N1-specific vaccine be required. Still, time is critical in vaccine development, and competing demands—like seasonal flu vaccination—can slow progress.

Lessons Learned From COVID-19
Experts warn that the lessons learned from COVID-19 regarding pandemic preparedness have not been fully implemented. Surveillance remains patchy, the CDC cannot conduct farm-level testing without state invitation, and centralized response systems are still lacking. On the positive side, the federal government is offering financial incentives of up to $28,000 per farm for livestock operations that participate in surveillance and testing.

What Producers Can Do Now
• Tighten biosecurity: Limit traffic onto farms, disinfect vehicles and equipment, and require staff to change clothes and footwear before entering poultry houses.
• Monitor flocks closely: Report unexplained illness or deaths immediately.
Remember that even subtle symptoms may indicate infection.
• Separate poultry from wild birds: Prevent contact with waterfowl and avoid feeding practices that attract wild birds.
• Protect workers: Provide and train staff in the use of N95 masks, gloves, and other protective equipment.
• Stay informed: USDA, state ag departments, and university extension services regularly issue HPAI updates and resources.

Looking Ahead
H5N1 is both an animal health crisis and a potential public health emergency. For U.S. poultry producers, the priority is protecting flocks through robust biosecurity and early detection and reporting. At the same time, collaboration with public health officials, veterinarians, and the broader agricultural community is crucial to mitigate risks for both animals and humans.

The virus’s adaptability is a stark reminder of the close ties between wildlife, livestock, and human health. By staying proactive now, producers play a key role not only in safeguarding their own operations but in preventing the next pandemic. If you need assistance with your biosecurity plan, please contact the experts at Sioux Nation Ag Center.