Assessing the Impact of COVID-19 Vaccination Programs on the Reduction of COVID-19 Cases: A Systematic Literature Review.

Background: Vaccination is the most effective way to prevent serious illness and death from COVID-19 among the various preventive interventions available. Objective: This review aimed to assess the actual effectiveness of COVID-19 vaccines in curbing the transmission and incidence of COVID-19 cases, to examine the role of different vaccine types in controlling the COVID-19 pandemic, as well as to identify the key factors influencing the efficacy of COVID-19 vaccines in containing the spread of the virus. Methods: The suggestions made by the PRISMA Framework were adhered to. To find the publications for the 2020-2023 timeframe, searches were performed through the PubMed databases, EMBASE, Scopus, and ProQuest. For the review, 17 reports satisfied the inclusion requirements. Ad26.CoV2.S or ChAdOx1-S, Gam-COVID-Vac(GAM), Sinovac Life Sciences Co., Oxford-AstraZeneca, Pfizer-BioNTech, and viral vector vaccines are among the vaccines that act on various variations. They dealt with the Delta, B.1.1.519, Omicron, and Alpha variations. Findings: Vaccinations against various Variants resulted in fewer COVID-19 infections, fewer deaths, and fewer hospitalizations. The emergency of the Delta variant, persons over 60, and vaccine hesitancy were the main issues affecting the effectiveness of COVID-19 vaccinations in containing the virus's spread. Conclusion: The collective evidence strongly supports the conclusion that COVID-19 vaccination plays a crucial role in mitigating the spread of the virus and reducing the severity of illness among those who contract the virus.