At the height of the pandemic, Florida Governor Ron DeSantis repeatedly promoted COVID-19 vaccines, saying correctly that "they're safe, they're effective," and they "are saving lives." With hundreds of millions of shots given worldwide at this point, the extensive international data on the vaccines' safety and efficacy have strongly and consistently backed DeSantis' statements. The vaccines are estimated to have saved over 14 million lives in 185 countries just in the pandemic's first two years.

But amid growing rumors of a 2024 presidential bid, DeSantis reversed his stance on the life-saving shots, abruptly questioning their efficacy and making unfounded claims about their safety. In December, his about-face culminated in a call for a grand jury to investigate any alleged "crimes and wrongdoing" related to the vaccines.

Though the swing appears more aimed at scoring political points than protecting Floridians' health, DeSantis' hand-picked surgeon general, Joseph Ladapo, has hewed closely to the governor's anti-vaccine rhetoric and health misinformation. Since his appointment as Florida's top doctor in late 2021, Ladapo has made false claims about vaccines, encouraged vaccine hesitancy, opposed masks, downplayed the health effects of COVID-19, and promoted ineffective COVID-19 treatments, such as ivermectin.

Ladapo's latest headline-grabbing anti-public health efforts came last October as he touted a dubious analysis that claimed mRNA COVID-19 vaccines are linked to an increased risk of cardiac-related deaths in males ages 18 to 39. The analysis—which was not peer-reviewed or published in any scientific publication and lists no authors—was widely panned by scientists and health experts, who called it "utter rubbish," "extremely misleading," and "comically bad." One of Ladapo's former mentors at Harvard told The Washington Post: "If I was a reviewer at a journal, I would recommend rejecting it." Politico, meanwhile, reported that a tipster alleged Ladapo "manipulated data" and committed "scientific fraud" to arrive at the false conclusion, which he used as the basis for a statewide recommendation against mRNA COVID-19 vaccination in young men.

Agency smackdown

But Ladapo's efforts to thwart public health didn't stop at Florida's borders—the internal medicine doctor took his COVID-19 misinformation right to the Food and Drug Administration and the Centers for Disease Control and Prevention. And the agencies responded in kind.

In a four-page letter dated March 10, FDA Commissioner Robert Califf and CDC Director Rochelle Walensky easily debunk his inaccuracies, falsehoods, and bluster, while taking the opportunity to point out that he is failing the people of Florida in his role as a public health official.

The two federal officials started by schooling Ladapo on the many safety-monitoring systems that the federal government has to track side effects and potential rare outcomes from vaccines. Like many anti-vaccine advocates, Ladapo parroted misunderstandings and inaccuracies about one particular system, called VAERS—short for the Vaccine Adverse Event Reporting System. This is an open system in which anyone—doctors, vaccine makers, members of the public—can report a health problem if they think there is any chance the problem is linked to a vaccination. Anti-vaccine advocates commonly point people to this system, holding up the unverified reports as evidence of vaccine harms, spurring fear and vaccine hesitancy.

But, of course, just because someone reported a health problem to VAERS doesn't mean that a vaccine actually caused the problem, Walensky and Califf note. In some cases, doctors and vaccine makers are federally required to report certain events after vaccination, regardless of whether they think the vaccine was the cause. To figure out causation, doctors at the FDA and CDC continuously comb through and investigate the reports, sometimes diving into patients' comprehensive medical records. And, in fact, most of the reports turn out to just be noise.

"Most reports do not represent adverse events caused by the vaccine and instead represent a pre-existing condition that preceded vaccination or an underlying medical condition that precipitated the event," Walensky and Califf noted. In cases that aren't so easily explained, the CDC and FDA compare the rate of unexpected health problems among vaccinated people to background rates in the population. This allows them to tell if there are more cases than would normally be expected if it weren't for the vaccine. Rate comparison is how, for instance, cases of myocarditis and pericarditis (inflammation of the heart muscle and surrounding tissue) were identified as rare (though still typically mild) side effects of mRNA COVID-19 vaccines.

Deadly misinformation

Like any medical intervention, COVID-19 vaccines do have some risks, and there are such rare events. However, the benefits clearly outweigh the risks, and the risks that do exist are not the ones Ladapo claims.

In a knock to Ladapo's dubious analysis on cardiac deaths, Walensky and Califf cited several studies that collectively indicate that "not only is there no evidence of increased risk of death following mRNA vaccines, but available data have shown quite the opposite: that being up to date on vaccinations saves lives compared to individuals who did not get vaccinated." They also specifically highlighted a study looking at cardiac events, noting that "the risk of stroke and heart attack was actually lower in people who had been vaccinated, not higher" (emphasis theirs).

Currently, the CDC estimates that unvaccinated people are nearly 10 times more likely to die from COVID-19 than people who are up to date on their vaccines. People who are vaccinated but have not gotten a bivalent booster are 2.4 times more likely to die from COVID-19 than people who are up to date.

And with this information, Walensky and Califf not-so-subtly suggested that Ladapo's shenanigans are fueling vaccine hesitancy, thus making him bad at his job. "Misleading people by overstating the risks, or emphasizing the risks without acknowledging the overwhelming benefits," causes vaccine hesitancy and needlessly puts people at risk of death or serious illness, they wrote. And this is clearly a problem in Florida, they added, writing:

As the leading public health official in [your] state, you are likely aware that seniors in Florida are under-vaccinated, with just 29 percent of seniors having received an updated bivalent vaccine, compared to the national average of 41 percent coverage in seniors. It is the job of public health officials around the country to protect the lives of the populations they serve, particularly the vulnerable. Fueling vaccine hesitancy undermines this effort (emphasis theirs).