SARS-CoV-2 Vaccine Against Virus: Mission Accomplished!?

ABSTRACT

Since the beginning of the COVID-19 pandemic in late 2019, SARS-CoV-2 has started to optimize itself. After crossing the species barrier between bats and humans, it has developed mutations in the viral spike protein, in particular at positions 69/70, 452, 501, 614, and 681, that enhance binding to the ACE-2 receptor and entry into host cells, thereby promoting viral transmissibility and pathogenesis. Mutations at positions 417 and 484 have begun to undermine the effectiveness of convalescent plasma, monoclonal antibodies, and currently available vaccines. The targeted and convergent evolution of SARS-CoV-2, which occurred despite the proofreading activity of the exonuclease, has resulted so far in five variants of concern, which have replaced previous strains. This calls for a worldwide surveillance of viral evolution including animal transmission and the development of vaccines responding to escape variants and inducing mucosal immunity. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.