An American virologist has developed a “beer vaccine” against a potentially dangerous virus… and tested it on himself. The experiment, daring and very limited on an ethical level, seems to have triggered an immune response, without us yet knowing whether it really protects against the disease.
Christopher Buck, a polyomavirus specialist at the National Cancer Institute, has been working for years on a vaccine against Betapolyomavirus hominis –formerly BK virus– involved in certain kidney, bladder, cerebral and cardiovascular diseases, particularly in transplant patients. In December, he decided to take it a step further by turning his research into a scientific brewing experiment: a beer brewed with genetically modified yeast capable of triggering an immune response.
The principle is as simple in theory as it is sophisticated in practice: using live yeasts – the same ones that ferment beer – as an edible vaccine vector. Christopher Buck modified brewer’s yeast to produce empty particles that mimic the surface of the virus, based on a protein in its coat; these pseudo-particles, non-infectious, serve as an alarm signal to the immune system, summarizes an article in the Smithsonian Magazine.
Before using it as a “therapeutic aperitif”, the team had already tested this device in mice: animals fed with live yeast producing these viral particles had developed antibodies directed against the Betapolyomavirus hominis. The researchers’ hypothesis is that yeast protects viral proteins from stomach acid, allowing them to reach the intestine, where immune cells learn to recognize them.
With these results, Christopher Buck decided to test his little preparation… on himself. A home brewer for around thirty years, he prepared a beer in his own kitchen containing these modified yeasts, which he describes as one of the best brews of his career. In May 2025, he drank a pint a day for five days, then repeated this five-day protocol twice, seven weeks apart, like vaccine boosters.
Anyone can cook
At each stage, the virologist took a few drops of blood to measure the appearance of antibodies. The analyzes show a clear increase in those directed against two subtypes of the targeted virus – the same as those suspected of being involved in certain bladder cancers – while its pre-existing antibodies against another subtype remain stable. In an article posted on the Zenodo pre-publication platform, Christopher Buck and his brother, also involved in the experiment, claim to have observed no notable adverse effects.
On an institutional level, however, the maneuver resembles a complete circumvention of the usual safeguards. An ethics committee at the National Institutes of Health (NIH) had forbidden the scientist from becoming a guinea pig in his own experiment; Christopher Buck then created a small non-profit organization, Gusteau Research Corporation – a nod to Auguste Gusteau, the head of the film Ratatouille whose motto is “Anyone can cook”–, in order to conduct the experiment as a simple citizen, outside the scope of the NIH. A trickster maneuver.
Unsurprisingly, this “vaccine beer” is raising eyebrows in the scientific community. Virologist Michael Imperiale of the University of Michigan points out that the experiment was based on a tiny sample and that possible side effects were not defined or systematically researched. Bioethicist Arthur Caplan, of New York University, is concerned about a counterproductive effect on confidence in vaccines: this artisanal approach could feed the dangerous idea that immunization is an individual DIY rather than a rigorously supervised collective process.
Christopher Buck takes a more optimistic view of edible vaccines. In his texts and videos published online, he emphasizes the potential benefit of “food” vaccines that are easy to produce, inexpensive, painless and potentially more acceptable to populations resistant to injections. Beer is, according to him, just one support among others: any food incorporating modified live yeasts could in theory serve as a vector, like bread for example.
For now, “beer-vaccine” only proves one thing: it is possible, in at least one person, to trigger a measurable immune response by drinking a drink fermented with vaccinating yeasts. But the authors themselves recognize that numerous safety and effectiveness tests remain necessary before imagining transforming this laboratory provocation into a real health product, whether targeting the Betapolyomavirus hominisflu, Covid-19 or other infections that they say they already have in their sights.
