Vaccine equity and access: A comparative assessment of Covaxin, Covishield, and Sputnik V.

Abstract

The RNA virus known as SARS-CoV-2, which causes severe acute respiratory syndrome, was discovered for the first time in Wuhan, China, in December 2019. The World Health Organization (WHO) declared the outbreak a global pandemic on March 11, 2020, as a result of the virus's subsequent spread throughout the planet. The urgent creation of safe and effective vaccines has elevated to a top priority in the global healthcare industry because of the terrible effects of the COVID-19 outbreak. The Covaxin and Covishield vaccines were administered as part of the start of the SARS-CoV-2 vaccination campaign in India on January 13, 2021. Covaxin is made up of adjuvant-inactivated viral particles, whereas Covishield is an adenovirus vector-based vaccine. The utility and effectiveness of each vaccine are significantly influenced by its formulation, adjuvants, and mode of action. Vaccine efficacy depends on various factors, including the creation of memory cells, cell-mediated immunity, and antibodies. Results from third-phase trials have shown that Covishield exhibits an effectiveness of approximately 90%, while Covaxin demonstrates an effectiveness of around 80%. Both vaccines have demonstrated satisfactory efficacy against several mutant variants of SARS-CoV-2. The effectiveness of Covishield, however, should be noted as compromised if there are significant changes in the spike (S) protein structure in future variants. In contrast, Covaxin may remain effective against such variants due to its ability to elicit multiple antibodies targeting different epitopes. The objective of this study is to evaluate and contrast Covaxin, Covishield & Sputnik v immunogenic and therapeutic efficacy. Additionally, potential vaccination challenges in the coming days will be discussed. Understanding the relative strengths and limitations of these vaccines can inform decision-making and strategies related to vaccine deployment, public health interventions, and future vaccine development efforts."