There is no evidence that mRNA Covid vaccines cause fatal cardiac arrest or other deadly heart problems in teens and young adults, a Centers for Disease Control and Prevention report published Thursday shows.
Ever since the vaccines from Pfizer and Moderna were authorized in late 2020, anti-vaccination groups in the U.S. have blamed the shots for fatal heart problems in young athletes.
One of the most notorious examples of vaccine misinformation involves Buffalo Bills safety Damar Hamlin, 26, who in 2023 collapsed on “Monday Night Football” as a result of cardiac arrest. Hamlin was resuscitated on the field and eventually recovered. He returned to play for the Bills last season.
“When Damar Hamlin went down, immediately comments were getting made that it was possibly vaccine-related,” said study co-author Dr. Paul Cieslak, the medical director of communicable diseases and immunizations at Oregon Health Authority’s public health division. “This is kind of what we were trying to address with this analysis.”
The findings in the new report come from the analysis of nearly 1,300 death certificates of Oregon residents ages 16 to 30 who died from any heart condition or unknown reasons between June 1, 2021, and Dec. 31, 2022.
During this time period, nearly 1 million teens and young adults in the state had gotten a Covid vaccine, the authors wrote.
The authors refined their focus to people who got an mRNA Covid vaccine from Pfizer or Moderna and died within 100 days of being vaccinated.
Out of 40 deaths that occurred among people who got an mRNA Covid vaccine, three occurred within that time frame.
Two of the deaths were attributed to chronic underlying health conditions.
The third death was recorded as an “undetermined natural cause,” with toxicology tests returning negative for alcohol, cannabis, methamphetamine or other illicit substances.
The medical examiner could neither confirm nor exclude Covid vaccination as the cause of death; however, none of the death certificates attributed the fatalities to the vaccines.
While it remains unclear whether the vaccine caused the third death, Cieslak noted that the analysis showed that 30 people died from Covid during the time frame, the majority of whom were not vaccinated.
“When you’re balancing risks and benefits, you have to look at that and go, ‘You got to bet on the vaccine,’” he said.
Dr. Leslie Cooper, chair of the cardiology department at the Mayo Clinic, who was not involved in the study, said the researchers were actually “quite generous” in their analysis, adding that the 100-day time frame following vaccination was a large one.
“They went above and beyond to try and capture any possible cardiac death from vaccinations,” he said.
Cardiac arrest occurs when the heart stops beating and pumping blood to the rest of the body. It’s not the same as a heart attack, which happens when blood flow to the heart’s muscle becomes limited or blocked, or myocarditis, which is an inflammation of the heart muscle.
For people under 35, the causes of cardiac arrest are often unclear. It could be the result of genetic defects or heart malfunctions, such as problems with the valves of the heart.
Even with the lengthy time frame, Cooper added, the analysis shows that the risk of sudden death in young adults after being vaccinated is significantly lower than the risk of sudden cardiac death from all causes — about 1 in 500,000 per year, compared to 1 in 100,000 per year, according to his estimates.
The data shows “no signal for any elevation in cardiac deaths associated with the Covid mRNA vaccines,” he said. “Their conclusions are quite reasonable.”
No vaccine has ever been conclusively linked to sudden cardiac death, said Dr. Ofer Levy, the director of the Precision Vaccines Program at Boston Children’s Hospital.
Although the mRNA vaccines have been linked to a small risk of myocarditis, the heart condition tends to be much milder than what is typically seen with traditional myocarditis from Covid infection, he added, and most people fully recover within a few days.
“This adds to evidence that people don’t drop dead from getting their mRNA Covid vaccines,” Levy said of the study.
