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SciCheck’s COVID-19/Vaccination Project

DeSantis’ Dubious COVID-19 Vaccine Claims


This article is available in both English and Español

While announcing a request for a grand jury probe into “crimes and wrongdoing” related to the COVID-19 vaccines, Florida Gov. Ron DeSantis and his panel of contrarian experts repeatedly suggested the shots were too risky. But such claims are unsupported and based on flawed analyses.

The vast majority of scientists, public health officials and other experts have endorsed the vaccines because the original randomized controlled trials and subsequent safety and effectiveness studies have shown the shots provide good protection against severe disease and death, with few safety concerns.

Although rare, the main serious side effect of the mRNA vaccines, which are the shots nearly all vaccinated Americans have received, is inflammation of the heart or its surrounding tissue, known as myocarditis or pericarditis. At 106 cases per million doses, the risk is highest for teenage males after the second dose, but is still rare, and most cases appear to resolve within a few months.

Facing a possible winter surge of COVID-19, public health experts have encouraged people, particularly higher risk individuals of any age and older folks, to get vaccinated with the omicron-updated bivalent boosters from Pfizer/BioNTech or Moderna. As of Dec. 14, fewer than 17% of American adults — and just over a third of those over 65 — have received an updated booster.

But in the state with the highest percentage of people over the age of 65, DeSantis and his cadre of invited experts did the opposite, casting doubt on the vaccines and playing up their risks in a Dec. 13 roundtable event.

“The safe and effective terminology that’s been used” is “a lie, it has to be,” said Dr. Joseph Fraiman, an emergency medicine physician in Louisiana, who was in attendance. 

Fraiman and others, including Florida Surgeon General Dr. Joseph Ladapo, whom we’ve written about before, cited various papers or analyses that they claim show evidence of vaccine harm. But as we’ll explain, those studies have been widely criticized — and don’t trump the vast body of other evidence demonstrating the safety of the vaccines.

DeSantis, who is viewed as a potential leading contender for the GOP’s 2024 presidential nomination, initially was supportive of the COVID-19 vaccines. But at the roundtable, he announced he was creating a new panel of experts to “counteract nonsense” from institutions such as the Centers for Disease Control and Prevention, Food and Drug Administration and the National Institutes of Health. 

He also said he was petitioning the state Supreme Court to impanel a grand jury “to investigate any and all wrongdoing in Florida with respect to COVID-19 vaccines.”

Dr. Anthony Fauci, the departing head of the National Institute of Allergy and Infectious Diseases, told CNN that he was baffled by DeSantis’ action.

“I mean, we have a vaccine that, unequivocally, is highly effective and safe and has saved literally millions of lives,” he said, citing a recent report from the Commonwealth Fund that found in the last two years, COVID-19 vaccination in the U.S. has prevented 3.2 million deaths, 18 million hospitalizations and saved more than $1 trillion in medical costs.

“Vaccines are lifesaving,” Fauci added.

Much of DeSantis’ court filing is dedicated to arguing that the vaccine makers and public health officials misled the public about the effectiveness of the shots in preventing transmission of the coronavirus. At one point, the filing misleadingly notes that “a Pfizer executive confirmed at a hearing in front of the European Parliament that the company did not test its COVID-19 vaccines before they entered the market to determine whether they prevented the transmission of COVID-19.”

Claims about this testimony were circulating online a few months ago. As we explained then, this is not the big reveal that some claim it to be. The clinical trials were designed to evaluate how well the vaccines protected against symptomatic disease, and authorities specifically stated that it was not known how well the vaccines prevented viral transmission. But in the months after the rollout, studies did show that the vaccine was working pretty well at preventing infection and spread of the virus. As immunity waned over time and with the arrival of new variants, though, this ability declined. Against the latest omicron subvariants, the vaccines still likely provide some protection against infection and transmission, even if it’s limited and temporary.

In the brief portion dedicated to claiming that the COVID-19 vaccines might not be safe enough, the petition cites a flawed analysis performed by the state of Florida and an unpublished Swiss report, which as Health Feedback has written, has been distorted before. The petition also disingenuously suggests that an increase in heart attack deaths in younger adults during the pandemic, as reported in one study, could be due to the vaccines. But the study never mentions vaccination as a possible cause. Rather, the “spikes in heart attack deaths have tracked with surges of COVID-19 infection,” the press release for the paper says, explaining that the increase is likely due to the coronavirus or to extra stress experienced during the pandemic.

Problematic Adverse Event Analysis

DeSantis and his experts primarily relied on two analyses to support their claim that the COVID-19 vaccines are more dangerous than medical authorities have let on. 

The first is a paper, co-authored by Fraiman, which reanalyzed data from the Pfizer and Moderna trials and claimed to find an alarming increase in serious adverse events of special interest in vaccine recipients compared with the placebo groups. Adverse events are health issues that occur following vaccination, but are not necessarily caused by vaccination.

The study was highly criticized when it was released as an unpublished preprint in June and after it was published in the journal Vaccine in August. 

“To our surprise, in the Pfizer trial — the first vaccine to go through — there was a 37% increase in the number of serious adverse events. That was never reported, not by the FDA, not by Pfizer,” Fraiman said of his study during the roundtable.

“It turns out, with both Pfizer and Moderna, we had a 1 in 800 risk of serious adverse events,” he added, saying that by comparison, “most people, the majority of people, don’t have a 1 in 800 chance of even being hospitalized” from COVID-19.

But as other factcheckers have reported, scientists have noted numerous problems with the paper. First, the authors focused their analysis on what are called serious adverse events of special interest, or serious AESIs, which include events that in theory might be related to vaccination. But the trial reported all serious adverse events, so the authors had to choose the events they thought corresponded to the ones of special interest. Some of the decisions, critics say, appear arbitrary or inconsistent, and therefore could have been cherry-picked.

Second, the analysis was based on the total number of adverse events, and not on the number of people who experienced the events, which is the approach the FDA uses. The authors didn’t have access to patient-level data from the trials, so they couldn’t do the analysis the way the FDA did, and they attempted to correct for this with a simple adjustment. Regardless, this is a dubious methodology that could easily inflate the figures, since someone who has two or three symptoms would be counted two or three times.

That is particularly relevant because the authors said they used a “simple harm-benefit framework to place our results in context,” and concluded the risk of serious adverse events of special interest is higher than the vaccines’ reductions in COVID-19 hospitalization. Again, this is flawed because adverse events were counted separately, even if a single person experienced several, whereas people who were hospitalized for COVID-19 and may have experienced multiple symptoms were only counted once. 

And as Susan Oliver, an Australian scientist who corrects misinformation on YouTube, has explained, it’s also an “apples to oranges” comparison because many of the adverse events would not be as severe as a COVID-19 hospitalization — and because while the entire vaccinated group received the vaccine, very few people were exposed to the coronavirus. This greatly underestimates the benefit of the vaccines.

Multiple outside observers have said the paper looks to be a case of data dredging or data fishing, when researchers arrive at incorrect results after analyzing data in a bunch of different ways. If someone digs through data long enough, they will find results that are statistically significant, even when that finding may not be real. That’s why scientists usually specify in advance how they plan to analyze the data.

It’s worth noting that even if taken at face value, the paper’s alleged findings are not as explosive as Fraiman says. For example, when analyzed individually, neither the Pfizer nor the Moderna trial shows a statistical difference in the number of serious adverse events of special interest among the vaccine and placebo groups. It’s only when the trials are combined that the authors claim to find a 43% increase in such events, or an extra 12.5 events per 10,000 people, among vaccine recipients.

Fraiman and his co-authors have argued that the criticisms of their paper are invalid, but Jeffrey Morris, director of the division of biostatistics at the University of Pennsylvania, told us in an email that he doesn’t find their response “sufficient or convincing.”

“I still think their selection of which events to include and how [they] reclassified/binned the events is dubious,” he said, but what “is really ridiculous is their portrayal of it as a valid risk benefit.”

Trial data can’t get at that, he explained, because the benefit of vaccination lasts a long time, and much of the benefit would occur outside of the trial, whereas most of the risks of the vaccine occur soon after vaccination and would be captured in the trial.

“Their argument that trial data is sufficient to capture the scope of benefit is laughably ridiculous, and not addressed in the response by the authors — and leads to an exceptionally skewed risk-benefit,” Morris said.

Flawed State of Florida Analysis

The second analysis the roundtable put forward as evidence of the vaccines’ danger is an unpublished report the state of Florida released in October that claimed to find “an 84% increase in the relative incidence of cardiac-related death among males 18-39 years old within 28 days following mRNA vaccination.”

But as experts told us at the time, the analysis, which was used to justify Florida’s decision to no longer recommend younger males receive mRNA COVID-19 vaccines, had major flaws.

Update, Jan. 5: A committee at the University of Florida College of Medicine, where Ladapo is on the faculty, also said in a report released in early January 2023 that the analysis was “seriously flawed” and should not have been used as the basis to recommend against vaccination.

Rather than compare deaths among vaccinated or unvaccinated people, the analysis only included people who died after vaccination and evaluated the potential risk of vaccination by looking at differences in the number of deaths during the first month after vaccination versus in a remaining 25-week period.

Florida Gov. Ron DeSantis speaks during a press conference before newly appointed state Surgeon General Dr. Joseph Ladapo in September 2021. Photo by Paul Hennessy/SOPA Images/LightRocket via Getty Images.

This unusual method, known as a self-controlled case series, can be a powerful tool, but also can be tricky to do, especially when dealing with a terminal event such as death. And in this case, experts in the method said the study didn’t account for the fact that when people receive multiple vaccine doses, they spend more time being within a month of vaccination than further out from vaccination. This can skew the result.

Notably, an analysis from the U.K.’s Office for National Statistics that used the same method, but avoided the problem with the Florida analysis, did not identify any increased risk of death after vaccination. 

During the roundtable, Ladapo acknowledged that the state’s analysis was “preliminary” and “not perfect,” but quickly pivoted to saying that no study was perfect, and calling the findings “remarkable.”

While myocarditis and pericarditis are real risks of the vaccines, particularly for younger males and after the second dose, studies have found that the conditions are still rare following vaccination — and rarely life-threatening. There is no reliable evidence that the vaccines have increased the risk of death for any population. Numerous teams of experts have concluded that to date, the benefits of the vaccine outweigh the risks, even for younger males.

“There is a large literature on the safety of mRNA vaccines, and recommendations should be based on a comprehensive overview of the available evidence, not any one single study (even less so if it is unpublished),” Paddy Farrington, an expert in self-controlled case series and a professor emeritus of statistics at the Open University in the U.K., told us in an email in October.

German Autopsy Study

Near the end of the roundtable, Ladapo announced a plan to conduct a surveillance study of myocarditis in people who die within a few weeks of COVID-19 vaccination using autopsy results. The study will be done in collaboration with the University of Florida, and the state’s health department will use “disease surveillance and vital statistics to assess such deaths,” according to the roundtable’s press release

Ladapo’s inspiration comes from a recently published study by scientists affiliated with Heidelberg University Hospital in Germany. The researchers examined autopsy data from 35 people who died unexpectedly within 20 days of COVID-19 vaccination and concluded that for five of them, vaccine-induced myocarditis represented the “likely or possible cause of death.”  

But as we and others have written, experts say there isn’t enough evidence to prove that their deaths were caused by the vaccine. (For more, see our story “Autopsy Study Doesn’t Show COVID-19 Vaccines Are Unsafe.”)

“The temporal association of lymphocytic myocarditis following vaccination suggests but does not prove causality,” Dr. Leslie T. Cooper Jr., a myocarditis expert and chair of the Department of Cardiology at the Mayo Clinic in Florida, told us in an email.

The autopsy study also can’t say how frequent vaccine-related myocarditis is or how often it is fatal. Other studies, however, indicate the condition is rare and deaths are exceedingly uncommon. One report from the CDC did not identify any deaths among more than 500 patients 12 to 29 years old who developed myocarditis following mRNA COVID-19 vaccination. And in February 2022, the agency presented data showing that after nearly 350 million doses administered across the population, 13 deaths involving myocarditis had been reported among people 30 years and younger who had received a first or second mRNA dose. None of the reported deaths, the CDC said, had been determined to be vaccine-related.

A study published this month from Hong Kong also found that out of 104 patients who were hospitalized with myocarditis within 28 days of vaccination with the Pfizer/BioNTech vaccine, one, or about 1%, died within six months of the diagnosis. Cooper said that other studies have found even lower mortality rates. Thus, while death can occur, he said, the risk is very low.

We reached out to the University of Florida to find more information about the planned study Ladapo announced, but a media representative said on Dec. 19 that the university was “still looking into this topic.”


Editor’s note: SciCheck’s articles correcting health misinformation are made possible by a grant from the Robert Wood Johnson Foundation. The foundation has no control over FactCheck.org’s editorial decisions, and the views expressed in our articles do not necessarily reflect the views of the foundation.