USDA Gives Conditional License for Bird Flu Vaccine Given to Chickens
by Natasha Hobley, Published March 2, 2025, www.TheVaccineReaction.org
The U.S. Department of Agriculture (USDA) has issued a conditional license approval for an inactivated avian flu (bird flu) vaccine to be administered to chickens eaten by Americans. The license is being granted due to H5N1 influenza virus infections spreading in U.S. poultry. The United States has avoided giving H5N1 vaccine to until now.
The license was granted to Zoetis, Inc. a New Jersey-based producer of medicine and vaccines for pets and livestock. The company is the largest animal drug and vaccine producer worldwide and was previously owned by Pfizer, Inc. Their bird flu vaccine contains a killed version of the H5N2 variant that the company developed in an effort to stop circulating variants of the H5N1 virus among poultry.1
H1N1 is a type A influenza virus that was associated with the “swine flu” pandemic of 2009 and is easily spread between humans.2 H5N1 is a type A influenza virus usually infecting birds that can rarely cause “bird flu” in humans, who come in direct contact with infected birds.3
A conditional license from the FDA does not mean that the bird flu vaccine is approved for commercial use or that poultry farmers can purchase it at this time. The manufacturer still will be required to receive final approval from the USDA before it can be used in commercial poultry.4 5
Five Drug Companies Developing mRNA Bird Flu Shots for Humans
There are five drug companies developing an H5N1 biological product labeled a “vaccine” using mRNA technology to prevent H5N1 infections in humans, including GlaxoSmithKline/CureVac; Sanofi, Moderna and Arcturus Therapeutics. The Arcturus Therapeutics product is a self-amplifying mRNA “vaccine” candidate currently in clinical trials funded by the Department of Health and Human Service’s (DHSS) Biomedical Advanced Research and Development Authority (BARDA).6
In the last days of the Biden administration, Moderna, Inc. was awarded a $590 million contract by BARDA to speed up development of influenza vaccines using mRNA technology, including one to prevent H5N1 bird flu.7 The government’s contract with Moderna is specifically to develop an mRNA bird flu biological product for humans that will be labeled as a vaccine, just like was done was with the mRNA COVID-19 biological product.8
At the end of February 2025, the Trump administration announced they will be re-evaluating the $590 million Moderna contract as part of a government push to examine government spending on mRNA-based products. Moderna has been under pressure to find new sources of revenue since its COVID vaccines sales have fallen sharply.9
China Unsuccessful in Vaccinating Chickens to Try to Prevent Bird Flu
China has tried and failed to control bird flu among chickens by vaccinating them. The World Health Organization (WHO) has warned that inappropriate use of avian flu vaccine in poultry has “serious human health implications” as the vaccination contributes to silent transmission of infection by asymptomatic birds.10
Even if the bird flu vaccine for chickens is officially licensed by the FDA, the commercial chicken industry has not been interested in years past. The U.S. is the second largest exporter of poultry products in the world, but many overseas trading partners won’t buy chickens that have been given bird flu vaccine. Studies have shown that vaccines may keep a chicken from developing severe disease, but will not prevent silent asymptomatic infections and transmission of the H5N1 virus to other chickens.11
The Congressional Chicken Caucus wrote to the USDA earlier this month to remind policymakers that “vaccinating any poultry sector—egg layers, turkeys, broilers, or ducks—will jeopardize the entire export market for all U.S. poultry products.”
The U.S. farmers emphasized that if they are unable to sell their chicken overseas, the U.S. would face a potential $10 billion-plus annual economic loss in trade.
Bird Flu Vaccines Being Tested in Cows As Virus Becomes More Prevalent in Animals
According to the USDA, bird flu has also moved beyond infecting chickens to infecting dairy cows. This could result in policies that require vaccination of other animals beyond birds. Several vaccines for bird flu are currently being tested in cows but, according to Professor Rodrigo Gallardo at the UC Davis School of Veterinary Medicine, several vaccines for bird flu are being tested in cows, but as with birds he said, “vaccination is like the last resort for the U.S.”11
In the past, American farmers have been able to curb the spread of sporadic bird flu to their flocks through culling infected chickens or taking biosecurity measures, such as limiting access to birds and having visitors wear protective clothing. However, news outlets are reporting that the H5N1 virus has become a “major” threat to both commercial and backyard flocks, rather than just causing occasional sporadic outbreaks. Experts blame this on the wider circulation of the bird flu virus, while previous outbreaks were linked to wild carrier birds who migrated through the U.S..11
The USDA reports that in the past 30 days alone, bird flu has been confirmed to be circulating in 134 commercial and backyard flocks, affecting 18.91 million birds.11
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