Heart Inflammation Risk for Young Men Higher After Vaccination Than After COVID-19: Study

Heart Inflammation Risk for Young Men Higher After Vaccination Than After COVID-19: Study
The Moderna COVID-19 vaccine is administered in Orange, Calif., on Dec. 16, 2020. (John Fredicks/The Epoch Times)
Zachary Stieber

The risk of heart inflammation is higher for men as old as 39 after Moderna COVID-19 vaccination than after COVID-19 infection, according to a new study.

Researchers in England analyzed hospital admissions with myocarditis, a form of health inflammation, among the vaccinated between Dec. 1, 2020, and Dec. 15, 2021.

They estimated that the second dose of Moderna’s vaccine, which is advised for a two-dose primary series, leads to 97 myocarditis cases per million above baseline in the first 28 days after vaccination for men younger than 40. That’s up from 16 additional cases per million of myocarditis after a positive COVID-19 test and before vaccination.

Researchers also estimated that a first dose of Pfizer’s vaccine led to four additional myocarditis events per million, and that a first dose of Moderna’s vaccine led to 14 additional myocarditis cases per million, in the males younger than 40. A second dose of Pfizer’s vaccine was associated with 14 additional myocarditis events per million in the age group.

Both the Moderna and Pfizer vaccines have long been associated with heart inflammation, but Moderna’s has been linked with much higher rates.

Moderna and Pfizer did not respond to requests for comment.

“Vaccine-associated myocarditis was largely restricted to men younger than 40 years with 1 exception; both younger men and women were at increased risk of myocarditis after a second dose of mRNA-1273,” the trade name for Moderna’s vaccine, the researchers said.

The study was published by the American Heart Association (pdf) in its journal Circulation.

Dr. Sanjay Verma, an American cardiologist, told The Epoch Times that the dozens of post-vaccination deaths from myocarditis found by the researchers contradict the repeated claims by U.S. officials that post-vaccination myocarditis is mild and generally resolves itself.

The researchers found that 51 patients died after the AstraZeneca jab and 49 died after the Pfizer shot. No Moderna recipients died from myocarditis within 28 days of admission. Most of those who died were middle-aged or elderly.

Dr. Vinay Prasad, a professor of epidemiology at the University of California, San Francisco, said on Twitter that the study provided more evidence for the argument that Moderna should be banned for those under 40.

Walid Gellad, a professor of medicine at the University of Pittsburgh, said that the U.S. Centers for Disease Control and Prevention’s advisory panel should directly address post-vaccination heart inflammation when it convenes in September to discuss future vaccination plans.


The study analyzed records for people aged 13 and older who received at least one dose of the Pfizer, Moderna, or AstraZeneca vaccines and were admitted to a hospital with or died from myocarditis in the December 2020 to December 2021 timeframe.

Some of the vaccinated tested positive for COVID-19 and suffered from myocarditis before getting a dose.

The researchers took the numbers and came up with incidence rate ratios, or risk estimates, for total population, and for each gender by age by slicing the population between those younger than 40 and those 40 and older.

Myocarditis and two other forms of heart inflammation, pericarditis and myopericarditis, are most prevalent among young people, particularly young males.

Studies and records from a number of countries, including the United States, show that young males are at higher risk from myocarditis after vaccination than COVID-19. Some of the research indicates that the vaccinated are at more risk from heart inflammation than the unvaccinated.

The English researchers found an elevated risk for heart inflammation after the first shot of AstraZeneca’s jab; the first, second, third shots of the Pfizer vaccine; and the second and third doses of the Moderna vaccine for the total population studied, but the risks were higher after a positive COVID-19 test before or after vaccination.

“We found that across this large dataset, the entire COVID-19-vaccinated population of England during an important 12-month period of the pandemic when the COVID-19 vaccines first became available, the risk of myocarditis following COVID-19 vaccination was quite small compared to the risk of myocarditis after COVID-19 infection,” Martina Patone, the lead author and a statistician at the Nuffield Department of Primary Health Care Sciences at the University of Oxford, said in a statement.

“It is important for the public to understand that myocarditis is rare, and the risk of developing myocarditis after a COVID-19 vaccine is also rare. This risk should be balanced against the benefits of the COVID-19 vaccines in preventing severe COVID-19 infection. It is also crucial to understand who is at a higher risk for myocarditis and which vaccine type is associated with increased myocarditis risk,” Nicholas Mills, a professor at the University of Edinburg and another author, said.

The research was funded by the United Kingdom government.

Enrico Trigoso contributed to this report.