Avian Flu Updates: Agriculture, Food Safety and Trade

By D'Lyn Ford

Avian flu’s implications for animal agriculture, the human food chain and international trade took center stage at an industry forum hosted by NC State University’s Food Animal Initiative (FAI). 

Scientists and state and federal officials provided updates on highly pathogenic avian influenza (HPAI) during the event at the North Carolina Biotechnology Center in Durham on April 22. Veterinarians and industry experts discussed biosecurity measures in the poultry, dairy and swine industries.

In North Carolina, where animal agriculture generates about 70% of the industry’s cash receipts, HPAI mitigation is a major concern. In U.S. rankings, North Carolina is No. 1 in cash receipts from all poultry and egg products, No. 2 in turkey production and annual pig crop, No. 3 in pigs and hogs, and No. 4 in broilers.  

The forum focused on HPAI’s significance for human and animal health, food safety and the U.S. economy. Experts also shared biosecurity, education and training resources for poultry, dairy and swine producers, which are listed below.

Poultry and Livestock

The current HPAI outbreak began in early 2022, when a new strain of the virus in migrating birds infected poultry and wild birds along the Atlantic Flyway in the eastern United States. 

In poultry, HPAI is a deadly and fast-spreading virus. To contain outbreaks, the U.S. has relied on culling infected flocks. 

HPAI has had the greatest impact on pullets and egg-laying poultry, where bird housing density is higher, said Dr. Lisa Rochette, a veterinarian with the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (USDA APHIS).

In the U.S., the current HPAI outbreak has affected 168.62 million birds since it began in February 2022, according to USDA APHIS records. The outbreak has involved 1,689 flocks, 781 of which were commercial and 908 of which were backyard flocks.

In March 2024, HPAI was detected in U.S. dairy cattle for the first time. Testing in April 2024 confirmed the virus in one herd in North Carolina.

“We’re very experienced in dealing with HPAI in poultry,” said Rochette, a North Carolina native based in Raleigh, North Carolina. “High-path in dairy cattle has been a worrying experience for all of us.”

To date, 1,025 U.S. dairy herds in 17 states have tested positive for HPAI. While the virus can cause illness in cows, they usually recover within a few weeks. 

The North Carolina dairy herd was isolated until it tested negative for the virus in late April 2024, and no subsequent cases in cows have been detected in the state. 

The first case of HPAI in pigs was reported in Oregon in late 2024 on a small farm. To date, no other HPAI cases have been confirmed in U.S. pigs.  

Human and Animal Health

For the general population, the risk of contracting HPAI is low. People who work in poultry or dairy operations or have backyard flocks are at higher risk. 

In all, 70 people in the U.S. have been infected with HPAI, almost all of whom were exposed during poultry culling or while working on dairy farms. Many experienced mild symptoms such as conjunctivitis, or pinkeye. One death from HPAI was reported in a Louisiana man with underlying health issues. 

No evidence has been found of person-to-person spread of HPAI, said Emily Herring, a public health veterinarian with the North Carolina Department of Health and Human Services (NC DHHS). Since 2022, the state has monitored 432 people for possible exposure and tested 33 with symptoms, but no one in North Carolina has tested positive for avian flu, she said.

North Carolina’s ongoing HPAI surveillance efforts include hospital and emergency room reporting, epidemiologists across the state, wastewater testing, and FluSurv-NET, a voluntary Centers for Disease Control and Prevention (CDC) program in some North Carolina hospitals, Herring said.

Food Safety

From farm to plate, the USDA, CDC, and Food and Drug Administration work in collaboration to detect and stop HPAI outbreaks, said Lee-Ann Jaykus, William Neal Reynolds Distinguished Professor Emeritus with NC State University.

Jaykus, a food virologist, has expertise in how viruses affect food safety. Fortunately, HPAI is “quite heat-sensitive,” she said. “It is clearly inactivated by pasteurization and cooking our food.”

It’s safe to consume pasteurized milk, products made with pasteurized milk, and eggs, poultry and meat that have been cooked thoroughly, Jaykus said.  

HPAI is one of many reasons to avoid raw or unpasteurized milk and dairy products. “Don’t drink raw milk,” Jaykus said. “Stay away from raw milk cheeses.”