Study of First Next Generation mRNA Bird Flu Shots in Cattle Published

Researchers at the University of Pennsylvania have published a study based on their experimental use of a next generation mRNA bird flu vaccine tested on cattle.¹ Last year, the U.S. Department of Agriculture (USDA) agreed to give the novel mRNA biological developed by the University of Pennsylvania to cattle in an attempt to protect dairy farmers from the avian influenza virus.²

While the study found that the mRNA bird flu shot protected calves from contracting avian influenza from infected mother’s milk, the study did not look into whether it protected adult dairy cows from bird flu.³ The study has not yet been peer reviewed.⁴

Only 10 Calves Were Given the Shot

The study injected only ten calves with a monovalent mRNA-LNP vaccine encoding HA from the clade 2.3.4.4b A/Astrakhan/3212/2020 virus. The calves were given two doses of 50 and 500 ug in a prime boost regimen. Calves given the 500 ug dose had significantly higher antibody levels than the calves given the 50 ug dose. The animals were all given a second booster dose that further raised antibodies.⁵

The shot used in the study was developed by using a seasonal bird flu mRNA shot and substituting the viral haemagglutinin gene with the current H1N1 influenza virus circulating on dairy farms.⁶

The efficacy of the biological was tested by feeding milk infected with the avian influenza virus to both vaccinated and unvaccinated calves via the intramammary route 49 days after administration of the shots. Viral titers in the milk ranged from, 10 ^{2.25 –}107.5 TCID50/ml^{.7 8}

The calves were evaluated by way of examining nasal secretions one, two, three, four and five days post infection. All unvaccinated calves had detectable viral titers on test days. Calves that received the mRNA shot only showed minimal amounts of the H1N1 virus one through six days after infection. Accordingly, the study showed that the mRNA shot reduced avian influenza virus shedding after infection in calves exposed to infected milk via intramammary route.⁹

Study Opens Door to More Bird Flu Shots for Livestock

Future studies are planned to determine whether the mRNA shot would protect against intramammary H1N1 infections in lactating cattle and what minimum level of dosage would provide protection.

The study has opened the door to more livestock being given mRNA biological products labeled as vaccines. The USDA has approved avian influenza vaccine for chickens, as well as, at least seven other vaccine candidates for trials this year.¹⁰

Congressional Bills Push Back

Efforts to prevent avian influenza infections in livestock are facing challenges as lawmakers have introduced at least 16 bills in 10 states to regulate what types of mRNA products that are labeled as vaccines can be given to livestock. Senator Doug Mastriano of Pennsylvania introduced the Food Purity Protection Act, which seeks to keep mRNA products labeled vaccines and related substances out of the food supply for humans.^{11 12}

Senator Mastriano said:

This is not just a hypothetical scenario; it’s a growing concern as scientific advancements blur the lines between medicine and agriculture. While biotechnology has its place, our food supply should never become a testing ground for experimental medical interventions.¹³

The U.S. Centers for Disease Control and Prevention (CDC) claim that mRNA biologicals do not alter DNA. Because livestock vaccines have a mandatory withdrawal period of at least 21 days before an animal is slaughtered, the USDA asserts that any mRNA biological remnants will be gone from the animal’s system prior to human consumption.¹⁴

At about the same time as the cattle study was released, the U.S. Department of Health and Human Services (DHHS) declared that it canceled a $766 million dollar contract with vaccine manufacturer Moderna to develop a mRNA bird flu shot for humans.¹⁵

DHHS communications director Andrew Nixon stated:

After a rigorous review, we concluded that continued investment in Moderna’s H5N1 mRNA vaccine was not scientifically or ethically justifiable. This is not simply about efficacy—it’s about safety, integrity, and trust. The reality is that mRNA technology remains under-tested, and we are not going to spend taxpayer dollars repeating the mistakes of the last administration, which concealed legitimate safety concerns from the public.

If questions about the safety of mRNA biologicals have prompted the federal government to halt the development of mRNA H1N1 vaccines for humans, there are legitimate questions about whether there should be stricter regulation of the introduction of these controversial biological products into food supplies consumed by humans.

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