Since the discovery of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus in December 2019, it has spread rapidly affecting numerous people globally and World Health Organization (WHO) has declared a pandemic in March 2020. As cases of COVID-19 continue to rise daily, there are increasing concerns and controversies regarding the best methods to curb the coronavirus pandemic. Since there are no proven drugs that are completely effective for prevention or treatment of SARS-CoV-2, vaccines are considered to be the most favorable choice to control the spread of this disease and reduce severe morbidity and mortality from COVID-19. Therefore, this evidence-based intensive literature review aims to further identify and thoroughly understand the mechanisms of actions of the primary vaccines developed against the SARS-CoV-2, aiming to provide the latest information available on current COVID-19 vaccines, touching on the viral characteristics of SARS-CoV-2, vaccine development and platforms which may be beneficial to the advancing research of novel SARS-CoV-2 vaccines.
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