The difference between RBD of SARS-CoV and SARS-CoV-2 is located at the C-terminus residues. This change has an important impact on the cross-reactivity of nAbs. This difference was observed using bioinformatic approaches of epitope analysis. The antibody epitope score of SARS-CoV-2 is higher than SARS-CoV. Moreover, compared with the conserved regions, the non-conserved regions had a significantly higher antibody epitope score indicating that non-conserved regions of spike proteins are much more antigenic. The non-conserved regions also showed significantly higher surface epitope accessibility scores suggesting an easier accessibility for antibody recognition of non-conserved regions. The divergence of spike proteins is considered as a major change in the antibody epitopes. The search for SARS-CoV-2 requires more effort than simply screening SARS-CoV antibodies [95].