Which of the following vaccine beliefs that routinely circulate on social media are true?

• COVID-19 vaccines will alter people’s DNA;
• COVID-19 vaccines contain microchips that could track people;
• COVID-19 vaccines contain the lung tissue of aborted fetuses;
• And COVID-19 vaccines can cause infertility, making it more difficult to get pregnant.

The answer is none of the above. They have been debunked by the scientific community. But a recent study exploring a possible link between misinformation and vaccine holdouts found that more than half of those surveyed couldn’t definitively say all of the claims were false.

Among respondents who did not mark any items as true, 70 percent reported being vaccinated,  according to researchers from Northeastern, Harvard, Northwestern, and Rutgers. For those who marked a single false item as accurate, 43 percent were vaccinated and 36 percent were not. In the group that thought multiple statements were true, a “staggering” 42 percent had not had their shots, researchers wrote in the study.

Overall, 20 percent of U.S. residents think that at least one of the four claims is accurate. Just who are these people? They run the gamut―from the poor and wealthy, those with a high school diploma and those pursuing graduate degrees, to men and women, the study found.

“Misinformation beliefs are circulating around enough to be consequential,” says David Lazer, university distinguished professor of political science and computer sciences at Northeastern, and one of the researchers who conducted the study.

“It is plausible that some of this is actually causing people not to be vaccinated,” Lazer says. 

Overall, a significant fraction of Americans firmly believe vaccine misinformation or engage in discussions about it on social media, researchers found. Besides online conspiracy theories, some are choosing not to get vaccinated because of broader concerns that aren’t tied specifically to the COVID-19 shots.

“There’s a lot of overlap between people who don’t get the flu shot and people who aren’t getting the COVID-19 shot, which suggests that there is something more structural going on here than beliefs regarding these particular vaccines,” Lazer says.

The early summer poll of 17,000 U.S. residents comes as the Delta variant of SARS-CoV-2, the virus that causes COVID-19, drives a nationwide increase in infections—a surge largely fueled by a significant number of unvaccinated individuals. As a result, the role of unvaccinated people is receiving more attention.

Centers for Disease Control and Prevention data shows that 50 percent of the U.S. population has been fully vaccinated as of August 7. An additional 90 million people are eligible for shots but have not received them. Some of the skittish include young mothers in child-bearing years.

The most prevalent misperception linked the COVID-19 vaccines to infertility, which researchers found troublesome. “It is a clear cause for concern that only 52 percent of respondents were able to identify this particular statement as false,” they wrote in the survey.

It may lend further credence to why mothers, especially those under 36 years old, remain significantly more wary about vaccines than fathers, as prior Northeastern studies have shown. “When we look at predictors of vaccine resistance, the misperception regarding fertility seems to be especially consequential,” says Lazer.

The CDC advises that expecting moms can receive a COVID-19 vaccine. “There is currently no evidence that any vaccines, including COVID-19 vaccines, cause fertility problems,” the federal health agency says.

The infertility claim was the most popular myth of the four (11 percent of all respondents believed it was true), followed by altering DNA (10 percent), aborted fetus tissue (9 percent), and microchips (8 percent).

Does believing vaccine misinformation necessarily lead to lower vaccination rates? There is a strong association, Lazer says, but the study can’t definitively determine cause and effect.

Overall, 80 percent of respondents did not mark any of the false statements as accurate, 9 percent reported believing one of the claims, while 10 percent believed two or more. 

“So far, we observe a consistent pattern―COVID-19 misperceptions and uncertainty seem to be linked to vaccination status,” they added.

There’s a difference between misinformation and outright misuse of information, Lazer points out. The former is evergreen and pops up again and again, unlike the latter which has a short shelf life.

When baseball legend Hank Aaron died in January of 2021 at the age of 86 from natural causes, “there was a big push on the anti-vax side to say ‘It was not a coincidence that Hank Aaron died two weeks after his vaccination,’” says Lazer, pointing out an example of opportunistic information misuse.

Researchers, however, remain focused on the broader implications for vaccine myths circulating in the public domain.

“People are being exposed to misinformation and that, in turn, may cause vaccine resistance or hesitance,” Lazer says.

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