PSMD1 and severe acute respiratory syndrome: Considering the efficacy of CCP in treating previous viral diseases such as the severe acute respiratory syndrome (SARS), 1918 flu epidemic, and H1N1 influenza (33–36), CCP, as a way of passive immunity, can provide NAbs that restrain the infection by binding to spike1-receptor binding protein (S1-RBD), S1-N-terminal domain, and S2, thus inhibiting virus entry and limiting viral amplification.