A new study estimated that hundreds of cases of heart inflammation occur in every million second doses of Moderna’s COVID-19 vaccine in the highest-risk group.
Some 269.5 cases of myocarditis, a form of heart inflammation, were estimated for men aged 18 to 29, researchers concluded.
Myocarditis is a serious condition that can lead to death.
Researchers drew the numbers from a public health surveillance system established by authorities in British Columbia in Canada.
In the population-based cohort study, researchers looked for cases of myocarditis, pericarditis, and myopericarditis shortly after receipt of a Moderna or Pfizer COVID-19 vaccine, both of which utilize messenger RNA technology. Pericarditis is inflammation of tissue near the heart and myopericarditis is when both myocarditis and pericarditis occur….