In May 2021 I was hospitalized and received treatment for myocarditis and pericarditis; In May 2021 I was hospitalized and received treatment for myocarditis and pericarditis; This spontaneous case was reported by a patient and describes the occurrence of MYOCARDITIS (In May 2021 I was hospitalized and received treatment for myocarditis and pericarditis) and PERICARDITIS (In May 2021 I was hospitalized and received treatment for myocarditis and pericarditis) in a  patient of an unknown age and gender who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis.     No Medical History information was reported.    On an unknown date, the patient received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. In May 2021, the patient experienced MYOCARDITIS (In May 2021 I was hospitalized and received treatment for myocarditis and pericarditis) (seriousness criteria hospitalization and medically significant) and PERICARDITIS (In May 2021 I was hospitalized and received treatment for myocarditis and pericarditis) (seriousness criteria hospitalization and medically significant). The patient was hospitalized on sometime in May 2021 due to MYOCARDITIS and PERICARDITIS. The patient was treated with Surgery (Surgery and drainage) for Myocarditis and Surgery (Surgery and drainage) for Pericarditis. At the time of the report, MYOCARDITIS (In May 2021 I was hospitalized and received treatment for myocarditis and pericarditis) and PERICARDITIS (In May 2021 I was hospitalized and received treatment for myocarditis and pericarditis) outcome was unknown.            No concomitant medication was reported.  The patient condition had recurred twice and was able to avoid a second surgery as patient body had responded well to the anti-inflammatory treatment, which was prescribed.  Company comment This is a Spontaneous case reported by a patient of an unknown age and gender, with no medical history reported, who experienced the expected and serious (due to medically significant and hospitalization), AESI of Myocarditis and Pericarditis. The patient received an unspecified dose of mRNA-1273 on an unknown date, thus, exact latency between vaccination and onset of the event could not be assessed. The patient was hospitalized and received treatment for myocarditis and pericarditis, including surgery and drainage of body fluid, shortly after vaccination. The patient's condition had recurred twice and was able to avoid a second surgery due to a good response after the anti-inflammatory treatment prescribed. No further information regarding cardiac studies was provided. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This is a Spontaneous case reported by a patient of an unknown age and gender, with no medical history reported, who experienced the expected and serious (due to medically significant and hospitalization), AESI of Myocarditis and Pericarditis. The patient received an unspecified dose of mRNA-1273 on an unknown date, thus, exact latency between vaccination and onset of the event could not be assessed. The patient was hospitalized and received treatment for myocarditis and pericarditis, including surgery and drainage of body fluid, shortly after vaccination. The patient's condition had recurred twice and was able to avoid a second surgery due to a good response after the anti-inflammatory treatment prescribed. No further information regarding cardiac studies was provided. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.