Fig. 1.

A schematic illustration of the characteristics of VOCs and the neutralization of approved antibodies and vaccine sera. a WHO has designated Alpha, Beta, Gamma, and Delta variants as Variants of Concern (VOC), and they are colored in red, light blue, dark blue, and white, respectively. Orange represents the original strain and yellow represents the super-variant (Lamada strain or other upcoming variant) with appalling infectivity and immune escape ability that may arise in the future. The missiles represent antibodies, and the houses represent host cells. The virus number of four variants in the cartoon is estimated according to the ratio of reproduction number (R0) of the variants to the original strain, and the number of viruses hit by missiles is estimated according to the immune escape ability [https://aci.health.nsw.gov.au/covid-19/critical-intelligence-unit/sars-cov-2-variants]. This cartoon depicts the characteristics including infectivity and immune escape ability of these VOCs. Infectivity: Delta> Alpha> Beta/ Gamma; immune escape ability: Beta/Gamma> Delta> Alpha. b Amino acid substitutions of four VOCs (Alpha, Beta, Gamma, and Delta variants) in spike protein that can cause immune escape. c Amino acid substitutions of four VOCs (Alpha, Beta, Gamma, and Delta variants) in spike protein that enhance the infectivity. d The neutralizations of four RBD-target antibodies (Bamlanivimab, Etesevimab, Casirivimab, and Imdevimab) (https://www.fda.gov) which have received emergency use authorization (EUA) for COVID-19 therapy, other four RBD-target antibodies (RBD-48, RBD-85, RBD-98, RBD-109) and four NTD-target antibodies (NTD-18, NTD-20, NTD-69, and NTD-71) isolated form convalescent sera against four VOCs and D614G mutant are displayed. The neutralizations against Alpha, Beta, Gamma, Delta variants, and D614G mutant are shown as red column, green column, blue column, purple column, and pink column respectively, the data are reproduced from the original article¹ with permissions. e The neutralizing abilities of BNT162b2-immune sera and AZD1222-immune sera obtained at different times after vaccination against different variants. 4 means all participants maintained neutralization ability, 3 means 75% participants maintained neutralization ability, 2 means 50% participants maintained neutralization ability, 1 means 25% participants maintained neutralization ability, the data are reproduced from the original article¹ with permissions