Fact Check-Vaccinated people are not ‘biological time bombs’ carrying coronavirus ‘super strains’

Updated to correct spelling of expert’s last name from fourth-to-last to second-to-last paragraphs

Contrary to claims made on a COVID-19 conspiracy theory blog, people who have received mRNA vaccines for the coronavirus do not pose a “threat to society” by “spreading their super strain viruses far and wide.”

An April 8 post on a WordPress blog called “Foreign Affairs Intelligence Council” (archived here ) makes several false claims about the coronavirus as well as the mRNA COVID-19 vaccines authorised for emergency use in the United States, namely that they are “experimental” and designed to transform recipients into “bioweapons factories.” The blog also alleges that vaccinated individuals are more likely to spread “super strain” variants that will kill the unvaccinated.

Social media posts sharing the link can be found here and here .


Reuters Fact Check previously debunked claims that the available COVID-19 vaccines are “experimental” (here). All current COVID-19 vaccines were put through standard safety testing before being rolled out to the public.  


Since the early months of the COVID-19 pandemic, conspiracy theorists have made baseless claims that the crisis was orchestrated by various people and entities, including Bill Gates (here) and the U.S. Center for Disease Control and Prevention (CDC)’s National Institutes of Health (NIH) (here).

Despite the blog’s claim that Dr. Anthony Fauci, the top U.S. infectious disease doctor, conspired with the Chinese Communist Party to build SARS-CoV-2, the virus that causes COVID-19, as a “deadly bioweapon” to “wipe out humanity,” Reuters has found no evidence to substantiate this conspiracy theory (here, here).


Without providing evidence, the blog post claims that vaccinated individuals are more likely to carry and spread virus variants because the purpose of mRNA vaccines is to “transform their bodies into bioweapons factories so that the mutation development could then proceed globally.” There is no scientific evidence to support this conclusion.

The U.S. Centers for Disease Control and Prevention (CDC) says, “a growing body of evidence suggests that fully vaccinated people are less likely to have asymptomatic infection” and are “potentially less likely to transmit SARS-CoV-2 to others” altogether (here).

The CDC also says that “further investigation is ongoing” and that “the risks of SARS-CoV-2 infection in fully vaccinated people cannot be completely eliminated as long as there is continued community transmission of the virus.”

There is no evidence that COVID-19 vaccinations have caused the original coronavirus to mutate. As explained here by the World Health Organization (WHO), when a virus is spreading widely in a population and infecting many people, it is more likely to mutate.

“The more opportunities a virus has to spread, the more it replicates – and the more opportunities it has to undergo changes,” the WHO says.

Over the past few months, new forms, or variants of the novel coronavirus have emerged, namely B.1.526 in New York (here), the B.1.351 strain in South Africa (here), the B.1.1.7 lineage in the United Kingdom (here), the P1 variant in Brazil (here) and B.1.617 in India (here).

These mutations took place in countries where the virus spread rapidly in populations that had not yet reached high percentages of vaccination.

As explained here by the CDC, “current data suggest that COVID-19 vaccines used in the United States should work against these variants.” The CDC says, however, that “evidence is limited on how the new COVID-19 variants will affect how COVID-19 vaccines work in real-world conditions.”

The blog post’s claim that vaccinated people are more likely to carry and spread the variants is false, according to Dr. Robert Bollinger, an infectious disease specialist at the Johns Hopkins University School of Medicine (here).

“Compared to unvaccinated people, vaccinated people are less likely to get infected by all of the strains, including the variants,” Bollinger told Reuters via email. “If they are less likely to get infected with variants, they are also less likely to spread variants,” he added.

Bollinger explained that variants are spreading quickly as new mutations develop because “unvaccinated people are getting infected and infecting unvaccinated people at a high rate.”

Contrary to what the blog claims, very few vaccinated people are getting infected with variants, as more than 99.9% of all variant infections are from or to unvaccinated people, Bollinger said (here).

Experts at the Meedan Health Desk, a global team of public health experts that has offered relevant COVID-19 information to journalists since the start of the pandemic, said several studies had identified a higher viral load, the amount of virus measured in the body, as “a driver for transmission.”

“Research suggests that vaccinated people may have a lower viral load compared to unvaccinated individuals who become infected,” the Health Desk explained.

Preliminary data from Israel (here), where about 57% of the country’s population has been vaccinated (here), shows that “infected vaccinated individuals may have a four-fold lower viral load, compared to infected unvaccinated individuals,” a finding that supports vaccination to curb the spread of COVID-19.

As explained here by the New York Times, the rise of SARS-CoV-2 variants puts the unvaccinated most at risk. The highly infectious B.1.1.7, for example, the U.K. variant that is now the most common source of new U.S. infections, “spreads quickly among the unvaccinated, potentially overwhelming hospitals in areas where cases are surging.”

Thus the blog’s warning that “anyone who wants to survive the killer ‘super strain’ wave that’s mutating right now in the bodies of the vaccinated must realize that staying away from vaccinated people may be a matter of life and death” is unfounded.

Stephen Kissler, a postdoctoral fellow in immunology and infectious diseases at the Harvard T. H. Chan School of Public Health (here), told Reuters via email that it is true that a vaccinated person is more likely to be infected by a variant than by a non-variant (also known as wild-type) of SARS-CoV-2.

“It depends a bit on what’s circulating in the vaccinated person’s local environment, but generally, if they have equal chances of exposure to both wild-type and variant, the variant is the one that’s more likely to break through,” Kissler said.

But echoing Bollinger, Kissler stressed that a vaccinated person is much less likely to get infected at all, by either the wild-type or a variant.

In other words, while a vaccinated person is more likely to be infected with a variant than wild-type SARS-CoV-2, a vaccinated person is much less likely to be infected with either the variant or the wild-type coronavirus than a person who is not vaccinated.


False. The mRNA COVID-19 vaccines made by Pfizer-BioNTech and Moderna are not “experimental.” The COVID-19 pandemic was not planned. Vaccinated people are not more likely to be infected with, or spread virus variants, than non-vaccinated people are.

This article was produced by the Reuters Fact Check team. Read more about our work to fact-check social media posts here .