KIR2DL1 and COVID-19: The KIR2DL1+HLA-C2+ combination without an activating counterpart of either KIR2DS1 (39.8 vs. 25.2%, p = 0.03, OR = 0.51, CI = 0.23–0.93) or KIR2DS5 (41.9 vs. 27.1%, p = 0.03, OR = 0.51, CI = 0.28–0.93) or both KIR2DS1 and KIR2DS5 were more frequent in mild COVID-19 cases than severe COVID-19 cases (36.6 vs. 23.4%, p = 0.04, OR = 0.53, CI = 0.29–0.98).