Abstract
The alarming onset of some cases of myocarditis and pericarditis following the administration of Pfizer-BioNTech and Moderna COVID-19 mRNA-based vaccines in adolescent males has recently been highlighted. All occurred after the second dose of the vaccine. Fortunately, none of patients were critically ill and each was discharged home. Owing to the possible link between these cases and vaccine administration, the US and European health regulators decided to continue to investigate the potential causal relationship between COVID-19 mRNA vaccines and myocarditis. In any case, none of the patients fulfilled the criteria for multi-system inflammatory syndrome or Kawasaki-like disease and there was no evidence of acute SARS-CoV-2 infection.