evidence: Cases of myocarditis and pericarditis have rarely been observed after COVID-19 vaccination in the United States and evidence from multiple vaccine safety monitoring systems in the United States and around the globe supports a causal association between mRNA COVID-19 vaccines (i.e., Moderna or Pfizer-BioNTech) and myocarditis and pericarditis. [...] Guidance for Clinicians - Report all cases of myocarditis and pericarditis after COVID-19 vaccination to the Vaccine Adverse Event Reporting System (VAERS). [...] - CDC: Myocarditis and Pericarditis After mRNA COVID-19 Vaccination - CDC: Investigating Long-Term Effects of Myocarditis - CDC: Vaccine Safety Publications - NIH: Myocarditis and Pericarditis - Frequently asked questions about VAERS reporting for COVID-19 vaccines - How to report an adverse event to VAERS