Myocarditis is an inflammatory cardiomyopathy, most frequently caused by viral agents, affecting 10-20 individuals per 100.000 each year in the general population [1]. Myocarditis (sometimes associated with pericarditis) following vaccine administration has been traditionally reported as a rare event, accounting for 0.1% of > 620.000 reports recorded at the Vaccine Adverse Event Reporting System (VAERS) over a period of 18 years [2]. Of note, most of the events occurred after administration of live-attenuated smallpox vaccine and less commonly after other vaccines, such as diphtheria, tetanus, and polio, influenza or hepatitis B [2].k
