KIR3DL1 and viral infectious disease: Several lines of evidence suggest a strong contribution of KIR–HLA molecules to the outcome and susceptibility of different viral infections [17,18,19,20], including HIV, Hepatitis B virus (HBV), and SARS-CoV-2, although some data on the contribution of activating and inhibitory KIRs are in contrast, probably related to the different populations analysed.