U.S. dairy, turkey, and egg industries have sent an urgent request to Agriculture Secretary Tom Vilsack for the U.S. Department of Agriculture (USDA) and its federal partners to support development of safe and effective H5Nx vaccinations for dairy cows, turkeys, and egg-laying hens to help mitigate the circulation of H5Nx in dairy herds and reduce the risk of spill-over of highly pathogenic avian influenza (HPAI) into commercial turkey flocks and egg layer operations.

According to USDA, nearly 101 million birds have been affected by HPAI in the U.S. since the onset of the outbreak in January 2022. In late March, the virus was discovered in dairy cattle, with USDA’s latest data showing 192 herds have been affected. Since 2022, 14 human cases have been reported, with the majority being more recently. Four of those cases were following exposure to dairy cows, and the remaining 10 were following exposure to poultry.

“As this outbreak of H5Nx continues to progress, it is clear that a new approach is needed. This includes the availability of animal vaccines effective against current and future strains of H5Nx that are necessary for a sustainable food supply as well as human and animal health,” leaders of the United Egg Producers, International Dairy Foods Association, National Milk Producers Federation and National Turkey Federation wrote in the letter.

The leaders noted that the ongoing outbreak is concerning, because it endangers workers and threatens the livelihoods of farmers and producers as well as the stability of the broader food supply.

“Efforts to manage H5Nx on farms can also have direct impacts on food prices for consumers, threatening to increase costs across the supply chain from farm to table,” they noted. “Furthermore, a widespread and circulating animal disease with no end in sight could eventually upend the balance of the overall farm economy, putting billions of dollars of bulk commodities, inputs and consumer products at risk.”

The groups stressed that vaccines must be economically feasible for farmers and operators and cannot be deployed without a comprehensive, science-based approach that includes a distribution strategy; concurrent comprehensive risk assessments, and a validated, risk-based surveillance strategy that has been agreed upon by the U.S.'s international trading partners.

More broadly, the leaders warned there are serious policy questions to answer related to domestic and international markets before a vaccine can be deployed.

“USDA must remain dedicated to engaging with our international trading partners to ensure our trade policies reflect the new realities of a world that is constantly combating H5Nx,” they wrote. “We have confidence that USDA and its federal partners—in consultation with leaders from our industries—can create a policy environment that is conducive to the continued free flow of U.S. dairy, turkey and egg product exports once H5Nx vaccines are available for deployment, but these international conversations must be accelerated.”

Even as the public and private sectors continue to work together to fight the virus, the groups said continued circulation of H5N1 “will remain a significant and imposing threat to our nation’s food security and, therefore, our national security.”

In a statement provided to Feedstuffs, a USDA spokesperson said the agency is leaving “no stone unturned in the fight against H5N1.”

Vaccine development is part of that effort, but the agency noted that, particularly for poultry, “a vaccination strategy would be challenging to implement domestically and would have significant trade ramifications that would affect poultry farmers and still may not be guaranteed to eliminate the virus.”

Calling the emergence of the virus in dairy cows “a unique event,” the spokesperson said research in bovine vaccines is promising but is in the early stage of development.

The agency emphasized the use of already available strategies, including strong biosecurity safeguards.

National Chicken Council maintains reservations

One group noticeably absent from the industry letter—as the broiler sector has also been affected by the disease—the National Chicken Council (NCC) told Feedstuffs that it maintains reservations about an HPAI vaccine as this still would not eliminate the virus and would also affect trade.

According to NCC, vaccinating commercial poultry will not eliminate HPAI circulating in and being spread through the wild bird population. It also will not keep dairy cows from being infected or keep all vaccinated birds free of the virus.

Even so, NCC said it will continue to encourage ongoing discussions and research regarding biosecurity practices to protect all poultry and a potential vaccination strategy that will not impact exports.

“We currently support USDA’s Animal & Plant Health Inspection Service (APHIS) ‘stamping out’ policy to eradicate the virus, and we believe that this is the best approach to eliminating HPAI in the U.S.,” NCC said. “We also encourage APHIS to continue to work with our trading partners to ensure that, should a vaccination strategy be deployed, we can continue to feed the world with safe, wholesome and affordable poultry products.”

Most countries, including the U.S., currently do not recognize countries that vaccinate as being free of HPAI due to concerns that vaccines can mask the presence of the disease. As such, these countries do not import from countries that vaccinate, NCC explained.

The U.S. broiler industry is the second-largest exporter of chicken in the world, exporting about 16% of U.S. chicken meat production valued at more than $5 billion annually. Regardless of which poultry sector chooses to vaccinate, NCC said the broiler industry would lose its ability to export, costing the industry and the U.S. economy “billions and billions of dollars every year.” It would also have a devastating impact on thousands of family farmers who raise the birds. 

Agencies sampling

The Food Safety & Inspection Service (FSIS) recently announced that, beginning Sept. 16, 2024, it will be adding H5N1 influenza A monitoring in dairy cows at slaughter to its already robust national surveillance programs for pathogens and chemical contaminants.  

FSIS said it will leverage its existing National Residue Program (NRP) and conduct H5N1 sampling in the muscle samples of dairy cow carcasses already collected for this program. Samples will be tested by FSIS laboratory personnel using polymerase chain reaction (PCR) testing. Carcasses sampled under the NRP will held by establishments pending results of residue testing. This process will not require additional holding time for carcasses beyond current residue testing protocols.

In the event of a positive H5N1 finding, USDA said it will work with industry to ensure the carcass does not enter the food supply. 

FSIS said it will keep stakeholders informed of the results of the H5N1 sampling. 

In early August, the Food & Drug Administration, National Conference on Interstate Milk Shipments (NCIMS) Executive Board and USDA informed State Departments of Agriculture and Departments of Health that they would soon begin seeking voluntary sampling after developing a silo sampling study to determine the presence and current nationwide prevalence of HPAI in bulk raw cow’s milk at dairy processing facilities.

“The goal for this effort is for NCIMS, FDA and USDA to work together to gather H5N1 prevalence data to evaluate and to make decisions that are data driven. State milk regulatory programs serve a vital role in this study and your state’s participation would be sincerely appreciated,” they wrote.