Since April 2021, there have been increased reports to the Vaccine Adverse Events Reporting System (VAERS) of cases of inflammation of the heart – called myocarditis and pericarditis – happening after mRNA COVID-19 vaccination (Moderna and Pfizer) in the United States.
Conclusions
Based on passive surveillance reporting in the US, the risk of myocarditis after receiving mRNA-based COVID-19 vaccines was increased across multiple age and sex strata and was highest after the second vaccination dose in adolescent males and young men.[/b]
