This is a literature report for the following literature source(s):  A 30-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: Bnt162b2 (dose 1, single), for COVID-19 immunization. The following information was reported: MYOCARDITIS (hospitalization, medically significant), 4 days after the suspect product(s) administration, outcome "recovered". The patient symptoms resolved on first day of hospitalization, and he was discharged on hospital day 3. The patient was hospitalized for myocarditis (hospitalization duration: 3 day(s)). The patient underwent the following laboratory tests and procedures: Coxsackie virus test: Negative; C-reactive protein: 129 mg/l, notes: notably elevated; 1.5 mg/l, notes: at follow up; Cytomegalovirus test: Negative; Echocardiogram: no regional wall motion abnormalities; Ejection fraction: 65-70 %, notes: normal; Electrocardiogram: T-wave inversions in lateral leads; resolved; Epstein-Barr virus test: Negative; Troponin I: 2447 pg/mL; 2518 pg/mL, notes: peak.  Discussion: This is among the first series to report multiple cases of myocarditis in adults following vaccination against SARS-CoV-2. All four patients were young, between 20 and 30. All presented with chest pain two to five days after their second vaccine dose. All had significantly elevated troponin-I levels. Myocarditis is most often caused by direct viral injury or by autoimmune mechanisms but has been sporadically linked to vaccination. Over 50 cases had been reported to the Vaccination Program. Myopericarditis has also been reported soon after vaccines against anthrax, hemophilus influenzae type b, hepatitis B virus, inactivated influenza, and live attenuated zoster vaccines. Neither clinical trial reported adverse cardiac events including myocarditis. As vaccination rates increase among younger patients, however, several cases of post-vaccine myocarditis are being reported in adolescents and young adults. In addition to these anecdotes, a multinational cohort study analyzed electronic health record databases and found the incidence of myocarditis and pericarditis among vaccine recipients aged 18 to 35 to be approximately 0.016% for women and 0.037% for men. The Centers for Disease Control and Prevention (CDC) has since warned clinicians to be wary of post-vaccine myocarditis in teens and young adults. It remains unclear why younger patients are more prone to develop this adverse effect. A possible explanation could be related to the stronger immune response in younger patients, which can also explain the higher prevalence of side effects to the vaccines in this patient population. While certainly a pattern worth exploring, this case series has numerous limitations, including a small sample size, variation in workup and treatment strategies, and retrospective analysis insufficient to establish causality. Nevertheless, the odds of incidental seronegative viral myocarditis occurring in four patients presenting to a single medical center within days of vaccine administration would be long. The authors encourage further investigation and reporting of potential cases of post-vaccine myocarditis.  Follow-up (30Mar2023 & 05Apr2023): This is a literature report from the Myocarditis following mRNA vaccination against SARS-CoV-2, a case series, This is a follow-up report based on the receipt of the publication; the case has been updated to include additional information identified in the publication; updated information: lab data details (CRP) and narrative; Sender's Comments: contributory role of the usage of the vaccine BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE), (Lot number and expiration date was not reported) to the reported events 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.