Comparative Efficacy of mRNA and Conventional Vaccines Against Viral Diseases: A Systematic Literature Review

Abstract

The rapid development and deployment of mRNA vaccines during the COVID-19 pandemic has prompted a critical need to systematically compare their efficacy and safety against conventional vaccine platforms across various viral diseases. This systematic literature review aims to synthesize and critically evaluate evidence on the comparative performance of mRNA and conventional vaccines, focusing on mechanisms of action, clinical outcomes, and future applications. We conducted a comprehensive search of peer-reviewed literature, applying predefined inclusion and exclusion criteria to identify studies that directly compared these vaccine types or reported robust efficacy data for individual platforms. Our analysis reveals that mRNA vaccines consistently induce potent humoral and cellular immune responses, often exceeding those of conventional platforms in terms of neutralizing antibody titers and T-cell activation; however, this superior immunogenicity is frequently accompanied by a higher incidence of transient reactogenicity. Conventional vaccines, including inactivated and viral vector formulations, demonstrate advantages in storage stability and lower manufacturing costs, and they remain highly effective, particularly against endemic viral diseases. The results further indicate that mRNA technology offers unparalleled flexibility for rapid antigen design, enabling swift adaptation to emerging pathogens, while conventional platforms benefit from decades of safety data and established production infrastructure. We conclude that no single platform universally outperforms the other; rather, the optimal choice depends on specific viral threats, target populations, and logistical constraints