The U.S. Department of Agriculture this week authorized the first field safety trial of a vaccine for bird flu in dairy cattle as industry groups press the Biden administration to address the worsening outbreak with "a new sense of urgency."
The field trial is "a significant step forward" in the development of a vaccine, Agriculture Secretary Tom Vilsack said Wednesday at the Farm Progress Show in Boone, Iowa. A number of companies have been working on a vaccine, Vilsack said, and the USDA approved the trial after one firm "presented sufficient information" to be cleared to advance development.
No further details were provided, though progress on an animal vaccine against H5N1 avian influenza could help prevent animal-to-human transmission and prevent the loss of more livestock. Thirteen people have tested positive for bird flu since April, with the virus rampaging poultry flocks and infecting dozens of dairy herds — if not more.
Farm groups had remained somewhat resistant to vaccination as a solution to controlling bird flu, expressing concerns about vaccine effectiveness and potential trade ramifications. Trading partners have been wary to accept immunized animals over concerns vaccines could “mask” an infection, and trade barriers have been a significant factor in delays in vaccine approval for poultry.
However, as the outbreak worsens, the industry is beginning to change its tune on vaccines. Dairy, egg and turkey producers wrote to Vilsack earlier this month asking the USDA to accelerate approval of a vaccine for cows and poultry.
"As this outbreak … continues to progress, it is clear that a new approach is needed," according to a letter signed by the International Dairy Foods Association, the National Milk Producers Federation, the National Turkey Federation and United Egg Producers.
Addressing the trade barriers that come with an animal vaccine rollout is expected to be easier for dairy compared to poultry, Vilsack said at the Farm Progress show. Dairy cows are vaccinated "for a lot of things," he said, and that "has not created a problem with trade" in the past.
The biggest hurdle for developing a vaccine for poultry or dairy is ensuring the immunization is both safe and effective, Vilsack said. In poultry, current vaccine options either provide limited protection or make it difficult to distinguish between a vaccinated and sick bird.
"We'll continue to have conversations with our trading partners to begin breaking down the barriers that do exist," Vilsack said. "So, if and when we have a vaccine that works for chickens [and] turkeys, we're in a position to use it.”
