People in Republican-voting states were more likely to report adverse events after receiving a Covid-19 vaccination than people living in Democratic-leaning states, a new analysis finds, suggesting that how people view their post-vaccine side effects or decide whether to report them may be shaped by their political views.
The cross-sectional study, published Friday in JAMA Network Open, looked at more than 620,000 entries in the Vaccine Adverse Event Reporting System from 2020 through 2022 and found that a 10% increase in ballots cast for a Republican in the last presidential election was associated with a 5% increase in the odds that an adverse event after Covid vaccination would be reported, a 25% increase in odds that a severe adverse event would be reported, and a 21% increase in the odds that any reported adverse event would be severe.
“It’s all part of this incredible polarization that’s politically charged,” Eric Topol, founder and director of the Scripps Research Translational Institute, told STAT. He was not involved in the study. “The fact that they’re reporting a significant increase in states that are Republican is just consistent with everything we’ve seen in the pandemic.”
In the grim calculus of Covid-19 deaths, there is already a well known red-blue state divide among Americans. More people died in states where more voters registered as Republicans, voted that way, and elected members of the Republican party. Counties in Donald Trump’s column in 2020 were much less likely to get Covid vaccinations than counties that voted for President Biden.
VAERS is a surveillance system created by the Food and Drug Administration and the Centers for Disease Control and Prevention that allows patients, doctors, and vaccine manufacturers to voluntarily report symptoms that occur after vaccination. That’s a weakness for establishing cause and effect, but it’s a strength for gauging people’s attitudes about their experience, David Asch, lead author of the new paper, told STAT.
“It’s probably a better measure of how motivated people are to report. And that was really what we were trying to study,” he said. “The anti-vaccine movement might have started out along libertarian lines like, ‘Let’s not have compulsory vaccination,’ but it gradually moved into thinking that either the vaccines weren’t effective or that they were unsafe. And so we wanted to look at whether people were reporting safety concerns.”
In the study, the authors also looked at flu vaccination reports to see if certain states had greater tendencies to report related to political affiliations. They found no link there, which fits with greater acceptance of flu shots than Covid vaccinations, Topol said.
“That’s telling because we’ve never seen the flu engender political divides like this,” Topol said. “Partisan use of the flu shots has not really been part of all the anti-vaccine efforts.”
Asked what can be learned from his research, Asch replied with what he called less of a lesson and more of a lament.
“I wish we could find some way to just take this out of the dark side of political polarization, because it’s not serving anybody,” he said. “To the extent that some groups may be aligning themselves with, let’s say, an anti-vaccine approach, [that] puts those individuals at risk and actually puts the people who live around them at risk.”