The US has so far avoided vaccinations as a strategy to eradicate poultry flu, and instead relies on infected flocks. Could that approach change quickly as an escalating outbreak increases egg prices and records high prices?
And why aren’t the vaccines already given as millions of herds die?
The Agriculture Bureau on Friday showed the strongest indication that the federal government may be shifting its strategy. The agency said it has granted a conditional license for the H5N2 bird influenza vaccine, which circulates between variants of the H5N1 virus, a strain that circulates between US H5N2 flocks. .
The license from New Jersey-based vaccine manufacturer Zoetis acknowledges that the vaccine meets requirements for “reasonable expectations” of USDA safety and efficacy, a company spokesperson said. I stated.
However, the USDA has stopped allowing doses to be distributed widely. The agency’s spokesperson said in an email statement that the conditional license does not mean that it has approved the vaccine for commercial use or that poultry farmers can currently purchase it. He said.
“This is the usual step in the research and development phase, not implementing a vaccine strategy,” a USDA spokesperson said.
Still, experts say the move suggests federal health officials may be looking at other tools, such as vaccines, to deal with the ongoing crisis. In December, the government expanded testing of the country’s milk supply.
As of Tuesday, more than 160 million chicken, turkeys, geese and other infected birds had euthanized, according to the Centers for Disease Control and Prevention. Although outbreaks occur in at least 972 dairy herds in 16 states, culling livestock is not a typical practice as it can recover from the disease.
Agriculture Secretary Brook Rollins is expected to announce a new strategy to combat the virus without commenting on whether the vaccine will play a role.
Carol Cardona, an avian health expert at the University of Minnesota, said many complications could arise when the federal government vaccinates poultry.
“When we talk about chicken, we talk about ducks and turkeys, chickens. It’s the chickens that we eat and the eggs that lay, and they’re all grouped together in terms of trade restrictions. There is,” she said.
According to Cardona, the broiler industry (the agricultural sector that grows chicken for meat consumption) is likely to be the most affected. She accounts for about 96% of the poultry industry and has a huge export market, she said. The broiler industry provides $449.5 billion in economic activity and $36.7 billion in government revenue, according to a report by the American Poultry Association, an industrial and trade group.
“The broiler industry will say, for their own benefit, ‘No, there’s no vaccine until there’s no egg layer left,'” Cardona said. “It’s an extreme position, but they did.”
Additionally, the federal government and manufacturers need to make enough vaccines to immunize poultry farms across the United States, and Cardona burned when it allowed the bird flu vaccine to be placed in the country’s stockpile in 2015. It was, but it has never been used. In January, the USDA said it would begin rebuilding its avian flu vaccine stockpiles for poultry.
“So when the announcement comes, we’re ready to get vaccinated, so people have to issue orders,” she said.
Daniel Perez, a poultry medicine expert at the University of Georgia’s School of Veterinary Medicine, is studying how influenza viruses jump from animals to humans, promoting silent spreads in which vaccinated poultry infects asymptomatic birds He said he was worried about doing so.
“Vaccinations can sometimes be considered a kind of double-edged sword,” Perez said. “They can control the disease, but at the same time, they may not be able to control the infection. Therefore, vaccinated animals may not show any signs of the disease.”
Not all vaccinated birds are protected, as seen in vaccinated humans, and not have the same level of protection as next, he said.
“When a high-pathway virus enters a vaccinated chicken facility, there may be these low levels of viral replication that ultimately promote the emergence of strains with mutations,” Perez said. Host range, viruses that can infect other species, including humans.
Cardona said it was “theoretical,” but there could be some vaccinated birds with “silent infections.”
However, she noted that the country has more resources to manage such scenarios than before.
“We have more labs and far more testing capabilities than we’ve returned when they were theorized as being a problem,” Cardona said.
Another consideration is likely to be the people vaccinating birds — farm workers, said William Schaffner, an infectious disease expert at Vanderbilt University Medical Center in Nashville, Tennessee. , which means that you are likely to need proper protection to ensure you are not infected with the virus.
Public health experts are concerned about the potential health risks for chicken and dairy workers who are close to animals and often work in dirty environments, he said.
Perez said there is ongoing research to provide massive poultry vaccinations via drinking water and reduce human exposure.
Another idea is for farm workers against the virus to be vaccinated, Schaffner said.
“Hazmat works very well in the hospital when you’re caring for patients, don’t work that well when you’re out on the farm,” he said.
Perez noted that influenza vaccines in poultry and humans are not very effective and use old techniques that usually take months to administer.
“I think we should use this crisis as an incentive to do more research into vaccine improvements,” he said.
This story originally appeared on nbcnews.com. Read more from NBC News:
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