Doctor falsely claims risk of myocarditis after mRNA vaccine is ‘1 per 30 dose’

By: Soham Shah
July 17 2023

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Doctor falsely claims risk of myocarditis after mRNA vaccine is ‘1 per 30 dose’


The Verdict False

The risk of myocarditis after mRNA vaccine is close to 12.6 per million and 35.6 cases per million for the Pfizer and Moderna vaccine respectively.

Claim ID 1c1dc282


A tweet claiming to show a Canadian nurse who died of cardiac arrest has gone viral. The tweet reads, "Women have same risk of COVID-19 mRNA vaccine myocarditis as men, 1 in 30 per vaccine dose, which increases risk of sudden death in sleep #DiedSuddenly #cdnpoli #ableg [sic].” Archive link of the post can be found here

mRNA vaccines like the Pfizer vaccine and the Moderna vaccine have been administered to people across the world against the coronavirus. These vaccines have been the target of many conspiracy theories. 

However, the claim that the risk of myocarditis is "1 in 30 per vaccine dose" is false.

In Fact

According to a study published by the American College of Cardiology, the per-dose rates of myocarditis (inflammation of the muscles in the heart) and pericarditis (swelling of the skin around the heart) combined were 35.6 cases per million for the Moderna vaccine and 12.6 per million for the Pfizer vaccine in Canada, where the study was conducted. This is much lower than the proportion claimed in the viral tweet.

Guy Witberg, MD, MPH, a cardiologist at Rabin Medical Center in Petah-Tikva, Israel, wrote in an editorial comment that, “[The study] should help put to rest ‘vaccine hesitancy’ due to concerns over cardiac adverse events.”

Similarly, another study published in The Lancet analyzed 15,148,369 people who received 10,631,554 doses of Pfizer or Moderna vaccines in the U.S. observed only 411 myocarditis or pericarditis events.

The WHO says that “the benefits of COVID-19 vaccinations outweigh the risks of getting ill with COVID-19,” as the risk of myocarditis is much higher after being infected by the coronavirus.

A study published by the American Heart Association (AHA) that analyzed 42,842,345 people who received COVID-19 vaccines in England concludes: “Overall, the risk of myocarditis is greater after SARS-CoV-2 infection than after COVID-19 vaccination.”

The CDC also continues to recommend COVID-19 vaccines. It says that the known risks of a COVID-19 infection “far outweigh the potential risks of having a rare adverse reaction to vaccination, including the possible risk of myocarditis or pericarditis.”

The Facebook post that the tweet refers to also makes no mention of the death being caused by a COVID-19 vaccine.

Multiple false claims about the COVID-19 vaccines have been fact-checked by Logically Facts. William Makis has also been fact-checked in the past for spreading false information about the COVID-19 vaccines.

The Verdict

Multiple scientific studies and experts have concluded that the risk of myocarditis is much less in magnitude than the ‘1 in 30 per vaccine dose’ claim. Also, William Makis has a history of spreading COVID-19 vaccine misinformation. Therefore, we are marking the claim as false. 

The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19, including symptoms, prevention, and available treatment, please refer to the World Health Organization or your national healthcare authority.

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Global Fact-Checks Completed

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