acute myocarditis 2 days after 2nd dose; Fever on day 1; This is a literature report.  A 35-year-old male patient received bnt162b2 (BNT162B2), as dose 2, single (Batch/Lot number: unknown) for covid-19 immunisation. The patient's relevant medical history and concomitant medications were not reported. Vaccination history included: Covid-19 vaccine (DOSE 1, SINGLE, Manufacturer unknown), for COVID-19 immunization.  The following information was reported: MYOCARDITIS (hospitalization, medically significant), outcome "recovered", described as "acute myocarditis 2 days after 2nd dose"; PYREXIA (non-serious), outcome "unknown", described as "Fever on day 1". The patient underwent the following laboratory tests and procedures: C-reactive protein: 9; Ejection fraction: 50 %, notes: lateral and inferolateral hypokinesia; Electrocardiogram: results below, notes: Diffuse ST segment elevation with depression in aVR; Magnetic resonance imaging: results below, notes: Edema delayed enhancement; SARS-CoV-2 test: negative; Troponin: 18; 29. Therapeutic measures were taken as a result of myocarditis, pyrexia.  Clinical course: Clinical course: The article describes 8 patients who were hospitalized with chest pain and who were diagnosed with myocarditis by laboratory and cardiac magnetic resonance imaging within 2 to 4 days of receiving either the BNT162b2 or mRNA-1273 vaccine. Patients provided written informed consent, and the collection of clinical cases followed local Institutional Review Board requirements. The data that support the findings of this study are available from the corresponding author on reasonable request. Two of the patients (patients 3 and 4) had previously been infected by SARS-CoV-2 without need for hospitalization. All individuals were otherwise healthy males between the ages of 21 and 56 years. All but 1 patient developed symptoms after their second dose. Systemic symptoms began within 24 hours after vaccine administration in 5 out of 8 patients, with chest pain presenting between 48 and 96 hours later. Chest pain was most commonly described as constant, nonpositional, and nonpleuritic (only patient 7 reported pericardial pain), consistent with acute myocarditis mainly without pericardial involvement. Troponin values were elevated in all individuals and appeared to peak the day after admission, whereas no patient had eosinophilia. All patients were tested and were negative for SARS-CoV-2. Left ventricular ejection fraction was reduced (<50%) in 2 of 8 (25%) patients with a median left ventricular ejection fraction of 51.5% (first to third quartile, 48% to 59%). All patients had resolution of their chest pain, were discharged from the hospital in stable condition, and were alive with preserved left ventricular ejection fraction at last contact. The temporal association between receiving an mRNA-based COVID-19 vaccine and the development of myocarditis is notable. Trials that tested the BNT162b2 and mRNA-1273 vaccines showed that systemic reactogenicity more often occurred after dose 2 and generally within 48 hours after vaccination. On average, our patients presented with symptoms of acute myocarditis 3 days after the second injection, and in 5 out of 8 patients fever appeared a day before, supporting the hypothesis that myocarditis could be an mRNA vaccine related adverse reaction. The patient was 4 days in intensive care; no inotropes or mechanical circulatory support; discharged stable. Therapeutic measures included non-steroidal anti-inflammatory drugs (NSAIDs).  SUSPECT PRODUCT is under agreement with BIONTECH SE.; Sender's Comments: Based on the known safety profile of the suspect drug and close temporal association, a causal relationship between BNT162b2, and the event myocarditis cannot be excluded. The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to regulatory authorities, Ethics Committees, and Investigators, as appropriate.