Researchers have closely studied what messaging can be effective in public health campaigns on COVID-19. But less is known about where vaccine skeptics are getting the information that guides their decisions.

A new report by researchers from several American universities finds that vaccine-resistant people have little trust in mainstream media—they either turn to conservative news outlets such as Fox and Newsmax or they avoid traditional news media altogether. The study finds that as many as 36% of those who opposed the COVID vaccine relied on Facebook as their only pandemic information source in the first half of 2021.

The study’s findings may be useful to public health officials who are trying to reach as broad an audience as possible, including those who lack trust in mainstream media, says one of the seven authors, Matthew Baum, the Marvin Kalb Professor of Global Communications at Harvard Kennedy School, based in the Shorenstein Center on Media, Politics and Public Policy. “While we cannot make causal claims with these data, we do see a clear positive association between vaccine resistance and reliance on conservative media outlets, like Fox and Newsmax, or on social media—most notably Facebook—as sources of COVID-related information,” Baum says.

Baum has been one of the academic leaders of the COVID States Project, which has surveyed thousands of people in all 50 U.S. states on pandemic-related attitudes and behaviors since shortly after the pandemic erupted in early 2020. Dozens of reports on these nearly monthly surveys, each polling more than 20,000 respondents, are collected on the COVID States Project website.

Matthew Baum headshot in front of a light blue backdrop.

“[W]e do see a clear positive association between vaccine resistance and reliance on conservative media outlets, like Fox and Newsmax, or on social media—most notably Facebook—as sources of COVID-related information.”

Matthew Baum

To understand where vaccine-hesitant people go for their health information, the scholars looked back at data from several of the project surveys as well as related surveys by other academic and political pollsters. The resulting paper, “Media Use and Vaccine Resistance,” was published in May in the journal PNAS Nexus, a year-old open-access publication of the Proceedings of the National Academy of Sciences that explores the boundaries between the sciences, engineering, and medicine.

In addition to Baum, the study’s authors are Jon Green and David Lazer from Northeastern University; James Druckman of Northwestern University; Katherine Ognyanova of Rutgers University; Matthew Simonson of the University of Pennsylvania; and Roy Perlis of Harvard Medical School.

The study looked closely at Facebook as a source of virus information—and as a way to reach vaccine resistors. The data show that respondents who rely only on Facebook are “consistently among the most vaccine resistant”—between a quarter and a third of them resisted vaccination. Those who relied on the conservative news site Newsmax were the least likely to get vaccinated, but the number of individuals in this group was small, at just 2% of those surveyed, whereas Facebook was the sole source for between 12-16% of respondents.

The authors also looked at respondents from early surveys who reported being unvaccinated and who then took part in a later survey to determine vaccine attitudes and media exposure. This analysis also found that “members of the ‘only Fox,’ ‘none of these,’ and ‘only Facebook’ media types … are significantly less likely to subsequently report being vaccinated” than other groups of media consumers such as those who watch CNN or MSNBC.

The researchers note that many of those who rely on social media for COVID-19 related information are often distrustful of, or simply not exposed to, such information from credible mainstream media sources that would encourage vaccination.

The authors conclude that “social media seems ripe as a mechanism through which to direct pro-vaccination messaging.”

Banner photograph by Anthony Behar/Sipa USA/AP Images; Portrait by Martha Stewart

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