FCGR2A and COVID-19: The specificities of the two SARS-CoV-2 IgG FcγR ELISAs in comparison with the Euroimmun SARS-CoV-2 IgG NCP ELISA (Table 3; Fig. S4) were evaluated using a priori SARS-CoV-2 IgG-negative serum panels acquired from symptom-free donors before the COVID-19 pandemic in Europe (Germany), Africa (Ghana, Madagascar, and Nigeria), Asia (Lao PDR), and South America (Colombia) (Table S2) (3).