Safety and Adverse Events Related to COVID-19 mRNA Vaccines; a Systematic Review

INTRODUCTION: Knowledge of vaccine-related adverse events is crucial as they are among the most ‎important factors ‎that cause hesitation in receiving vaccines. Therefore, we aimed to systematically ‎review the adverse events ‎related to the mRNA vaccines reported in the literature.‎ METHOD: A systematic literature search was carried out in the databases of Scopus, PubMed, ‎Cochrane, and Web ‎of Science. We selected original studies that explored the side effects of ‎mRNA ‎COVID-19 vaccines using a two-phase (title/abstract and full-text) screening process.‎ RESULTS: Cardiac ‎complications were the most commonly reported severe adverse events. It appeared that ‎systemic adverse reactions are more ‎common after the second dose of vaccines. The number of ‎adverse effects reported after the Pfizer vaccine was ‎higher than other vaccines, mostly due to its ‎earlier approval and more widespread use throughout the world. Cardiac adverse events had a ‎‎higher prevalence but no significant association has been found between COVID-19 mRNA vaccines ‎and cardiac ‎adverse events except for myopericarditis. ‎ CONCLUSION: Vaccines ‎play a crucial role in controlling the COVID-19 pandemic and decreasing ‎mortalities and the results of the present ‎review acknowledge the fact that the benefits outweigh the ‎adverse events of these vaccines.‎