On April 16, a Facebook user known for frequently spreading disinformation (1, 2, 3) published several posts about COVID-19 vaccines, claiming that vaccination against the coronavirus is dangerous for health. The posts include the following assertions:
- A study involving 99 million vaccinated people found that the vaccines increased the risk of myocarditis by 610%, cerebral venous sinus thrombosis by 323%, and Guillain-Barré syndrome by 249%;
- Another study, which analyzed 80 million people by comparing vaccinated and unvaccinated individuals, showed a sharp rise in heart attacks, strokes, coronary heart disease, and arrhythmias after vaccination;
- According to Dr. Mary Bowden, the FDA typically issues a Black Box Warning if more than five deaths occur due to a medical drug and removes a drug from the market if there are 50 deaths. Therefore, COVID vaccines should be removed from the market, since, according to the VAERS system, 38,000 people have died as a result of COVID-19 vaccination.
The posts about COVID-19 vaccines contain disinformation and data manipulation:
- According to the authors of the study involving 99 million vaccinated individuals, the serious side effects mentioned were extremely rare and appeared only after the first vaccine dose. Additionally, establishing a causal relationship between the side effects and the vaccine requires further research;
- The study of 80 million people identified only an increased risk of coronary artery disease (CAD). No increased risk of heart attack, arrhythmia, or stroke was detected after COVID-19 vaccination;
- The FDA does not set a specific number of deaths from a medical drug (e.g., 5 deaths) for issuing a Black Box Warning. Furthermore, the VAERS system may include unverified or inaccurate data and is not considered reliable evidence of vaccine complications.~
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The side effects identified in the study of 99 million vaccinated individuals are very rare, and determining a causal link with vaccination requires further research
The 2024 cohort study of 99 million vaccinated people examined adverse side effects found in this population.
Importantly, the study’s authors themselves emphasize the effectiveness of the vaccine and state that the serious side effects mentioned in the study were very rare and occurred only after the first dose of the vaccine.
One of the study’s co-authors, Anders Hviid, cited a case of acute inflammation of the brain and spinal cord. According to him, among 1.75 million vaccinated individuals, there was only one case of acute inflammation of the brain and spinal cord after the first dose of Moderna. Even assuming a causal link between Moderna’s first dose and the case, it remains an extremely rare occurrence that was detectable only due to the large scale of the study.
For comment, Myth Detector contacted allergist-immunologist Bidzina Kulumbegov. He confirmed that the study did indeed show an increased risk of some rare side effects, such as myocarditis, pericarditis, Guillain-Barré syndrome, and cerebral venous sinus thrombosis, following COVID-19 vaccination. However, he emphasized that “despite the increased risk, such cases are rare, and further analysis is needed to confirm a direct causal relationship between the vaccine and these events.”
It’s worth noting that myocarditis and pericarditis are recognized as potential side effects of the vaccine; however, they are rare. They can also occur following a COVID-19 infection itself, typically present in a mild form, and patients usually recover within a few days or weeks.
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It is false to claim that the study involving 80 million people revealed an increased risk of heart attack, arrhythmia, or stroke after COVID-19 vaccination
The second study, published in 2025, examined 80 million people and used Odds Ratio (OR) analysis rather than Observed-to-Expected (OE) ratio analysis. The odds ratio (OR) is a measure of the association between an exposure and an outcome, comparing the odds of a specific outcome occurring with the exposure to the odds of a specific outcome occurring without the exposure.
According to the study’s findings, the odds of coronary artery disease (CAD) were higher in the vaccinated group compared to the control group, particularly after the second dose of the Pfizer vaccine, which should be taken into account in the development of future vaccination technologies.
It is important to note that the author of the viral post claimed that the study showed a sharp rise in heart attacks, strokes, coronary heart disease, and arrhythmias after vaccination. This is disinformation. The study identified only an increased risk of coronary artery disease (CAD). The findings clearly state that there was no increased risk of heart attack, arrhythmia, or stroke following COVID-19 vaccination.
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The FDA does not set a specific number of deaths from a medical drug for issuing a Black Box Warning, and VAERS data is not evidence of vaccine complications
The claim made by anti-COVID vaccine doctor Mary Bowden that COVID-19 vaccines should be removed from the market because the FDA issues a Black Box Warning for drugs associated with more than five deaths and removes drugs from the market after 50 deaths is false.
Bowden uses as evidence death reports submitted to the VAERS system, which is a vaccine adverse event reporting database where vaccinated individuals or anyone else can report post-vaccination experiences. VAERS clearly states on its website that a report of an adverse event does not necessarily mean that the vaccine caused the event. VAERS data is not analyzed and may contain incomplete or inaccurate information or may simply reflect coincidence.
Read more about this topic in the article prepared by Myth Detector: What is VAERS and how reliable is it as a source?
As for the U.S. Food and Drug Administration’s (FDA) Black Box Warning, it is issued in three main circumstances: when a drug carries risks of life-threatening or disabling effects; when serious side effects can be reduced with cautious prescription and monitoring; and when safe use of the medication requires special restrictions, such as certified prescribers or hospital-only administration.
It is worth noting that the FDA does not issue a Black Box Warning based on a specific number of deaths; such a criterion does not exist. What matters is whether the risks of the medication outweigh the benefits, which is not the case with COVID-19 vaccines – the benefits clearly outweigh the risks.
For example, in 2008, the FDA issued a Black Box Warning for fluoroquinolone antibiotics due to an increased risk of tendinitis and tendon rupture. The FDA advised doctors to consider alternatives and to stop treatment in patients who developed tendon pain or inflammation during use. In this case, the reason for the warning was not death, but the risk of tendon rupture.
According to a 2022 study, over 400 medications carry a Black Box Warning.
About the source
Facebook user Maia Tvaltvadze regularly spreads anti-vaccine disinformation, conspiracy theories, and fake anti-Western content. Myth Detector has fact-checked her disinformation on multiple occasions in the past.
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