 The results of this study suggest that both mRNA-based and adenovirus-vectored vaccines are effective in preventing COVID-19. However, the mRNA-based vaccine has shown greater efficacy than the adenovirus-vectored vaccine after two doses. Additionally, the mRNA-based vaccine has fewer side effects compared to the adenovirus-vectored vaccine. This article was authored by Ali poor Muhammad, Muhammad Zarii, Saeed Grbani, and others.