Additionally, we investigated the influence on specific locations, KIR3DL1+/HLA-Bw4(80I)+, and in all patients with MERS-CoV infection, so we suggest that synergistic reactions of CTLs and NK cells can efficiently control MERS-CoV infection and replication, and that NK cell-mediated anti-MERS-CoV immune responses are primarily involved in severe infections according to the study of SARS-CoV-2 (Table 3). This evidence concerns the gene KIR3DL1 and infection.