Conspiracy theorists scaremonger over self-spreading vaccines

Masho Lomashvili


Disinformation actors are looking for new ways to revive engagement with Covid-19 vaccine conspiracies. And they’ve hit on a new narrative to scare their followers into fresh outrage. 

“The Threat of Self-Spreading Vaccines” reads the headline of one article that is doing the rounds on social media. It claims scientists are developing a new form of vaccination that requires only a fraction to be inoculated for the vaccine to  spread through the whole population. 

Before we start debunking the actual texts of these pseudoscientific articles, let’s first examine the concept of self-spreading vaccines. It’s the idea that vaccines themselves could be as contagious as the diseases they fight. Researchers are developing self-spreading vaccines for use on wildlife, to enable the spread of the vaccine through a given animal population while only having to vaccinate about 5% of animals. But such vaccines have never been used on humans.

The research into self-spreading vaccines first emerged in the 1980s, when a small number of scientists started thinking of ways to fight viruses at the source — by stopping them spreading among animals, with a mind to stopping animals transmitting these viruses to humans. 

The first and only field trial of transmissible vaccines was conducted in 1999 by José Manuel Sánchez-Vizcaíno who led a team of researchers to Isla del Aire in Spain. The vaccine was tested against two viral diseases in rabbits: Rabbit hemorrhagic disease and myxomatosis. Some 56% of the rabbits developed antibodies to both viruses, indicating that the vaccine had successfully spread.

I asked James Bull, a Professor in Molecular Biology at the University of Texas about this experiment. He noted that “There was nothing to suggest that the vaccine was harmful, but I doubt that the rabbits were studied in such detail that subtle effects would have been identified.”

Either way, due to the lack of interest and funding, the research around transmissible vaccines died out. Until a few years ago, when a small number of scientists, like Bull himself, revived the idea.

Scott Nuismer is a professor at the University of Idaho who conducts mathematical modeling studies of self-spreading vaccines, he has previously worked with Bull on an article that generated major media interest in the subject.

I asked him how close we are to developing safe self-spreading vaccines. He wrote back the following: “My best guess is that it will be at least five years until an effective self-spreading vaccine for ANIMALS can be developed. There are many challenges to making this technology work.”

Nusimer used his caps lock key to make an important point. Anti-vaccine groups are spreading false information that these vaccines are targeted at humans.

Neither Bull nor Nuismer have heard of anyone working on transmittable vaccines for humans. 

In the articles mentioned above, there are two main claims on which the misleading information is based.

One of the articles I came across claims that the “Defense Advanced Research Projects Agency (DARPA) is examining this technology for the U.S. military to protect against the West Africa Lassa fever, a virus spread by rats to humans. This project, it should be noted, does not require the consent of our military service men and women.”

Bull was a consultant on this project. “The plan is to engineer a rat virus to protect rats from acquiring the Lassa fever virus,” he says. “Humans would not be infected by the vaccine because they are not infected by the rat virus that would be used in the engineering. The rat vaccine has been made and is undergoing cage trials with the rats to see if it works.” He also clarified that this experiment is being done inside contained lab environments with “no chance of the virus getting out.”

Another of the articles claims that “in 2019 the U.K. government began exploring this technology to address seasonal flu. A research paper from Britain’s Department of Health and Social Care advised that university students could be an obvious target group.”

Nuismer told me that even though he has seen this being referenced repeatedly on websites spreading disinformation, he has “never seen any actual evidence that this paper actually exists.” Despite the theories proliferating online, there is simply no evidence to suggest that scientists and governments are plotting to use self-spreading vaccines on humans as a covert means to overcome opposition to vaccines.


The Shanghai government is calling on citizens to share “heartwarming” stories and photos about the grueling two-month lockdown they endured in the spring. The materials will then form a propaganda exhibition in August. During the lockdown, barely-suppressed fury and indignation at the seemingly endless containment measures flared up on social media. We covered the Shanghai lockdown as it happened — tracking the journey of one man as he made his frightening, desperate escape from the city, where people were starving, sleeping in tunnels, and locked in their homes for weeks on end. The city is currently living in fear of a new lockdown as millions of locals took mandatory tests this week in the sweltering heat, after a single case of the new Omicron subvariant was detected on July 8. 

Russia has triggered a special session of the Biological Weapons Convention, arguing — once again — that the US is running bioweapons labs in former Soviet countries. The decision will force international governments to discuss Russia’s debunked claims, which have formed a longstanding narrative in Russia’s disinformation offensive for years. Russian Channel One recently aired a story propagating a wide array of myths about American labs in Georgia; including the claim that tropical fever cases in Georgia were being spread by mosquitoes bred in a Tbilisi lab. We’ve been investigating this particular narrative for years — check out our story from 2018. Meanwhile, Ukrainian scientists and environmental groups are accusing Russia of “ecocide” — the massive destruction of habitats and biodiversity — and are looking for ways to prosecute Russia under international law for the ecological effects of its invasion. There is an ongoing fear that “the Russian army is trying to ‘poison and burden the civilian population with environmental disasters.’”

A German law firm has pushed out a press release claiming that mRNA vaccines could lead to a completely made-up disease called V-AIDS (Vaccine-Acquired Immune Deficiency Syndrome). The release was picked up by a leading German press agency, and then automatically disseminated to a number of leading media outlets before they were removed. The claim that Covid vaccines cause immune deficiency has been circling since the outset of the vaccine rollout, with anti-vaccine activists co-opting the AIDS crisis to spread fear and panic about immunization. The crushing irony about it — as we have previously discussed in this newsletter — is that often, anti-vaccine activists are also AIDS deniers, regularly sharing platforms with those who dispute and distort the facts around the disease. 


Covid bereavement could be its own looming health crisis. In the U.S., more than 9 million people have lost a close relative due to Covid, according to a new investigation by researchers at several U.S. universities. They describe Covid-19 as a “bad” death: “those that involve pain or discomfort and happen in isolation. Their unexpectedness also makes these deaths more distressing.” The collective grief experienced as a result of COVID-19 bereavement increases people’s risk of depression and can make them uniquely vulnerable to mental distress.

This newsletter is curated by Coda’s senior reporter Isobel Cockerell. Frankie Vetch contributed to this edition.