SARS-CoV-2(12) COVID-19(9) Pathogenesis(6) Varicella-zoster virus.(6) Cell fusion(6) host–microbe interactions(6) virus(6) Glycoproteins(6) coronavirus(5) Structure(5) pandemic(5) antibodies(4) Vaccine(4) Vaccines(4) defined(3) mutant viruses(3) neutralizing antibody(3) SARS-CoV-2 drug(3) restrict(3) vaccination(3) SARS-COV-2 infection(3) variants of concern(3) SARS-CoV(3) variants(3) MERS(3) Research(3) respiratory(3) Stage(3) problems(3) resolved(3)