Time course of SARS-CoV-2 IgG in eleven SARS-CoV-2-infected patients and five routine (R) patients (including four family members of SARS-CoV-2 patient no. 14) who were interested in their SARS-CoV-2 antibody status. A signal (S)/cut-off (CO) value ≥1 is considered as positive for SARS-CoV-2 IgG. The results of the Abbott assay (N protein as the epitope) can be found in the upper part of the figure; those of the Virion-Serion assay (S protein as the epitope) are given below. Results from the validation part of this study were included.