Additional file 1 of Sustained seropositivity up to 20.5 months after COVID-19

Additional file 1: Table S1. Association of baseline variables and comorbidities with levels of SARS-CoV-2 antibodies at time point 4 (January-February 2021) prior to the massive rollout of vaccination. Table S2. Seropositivity against the SARS-CoV-2 receptor-binding domain antigen from variants of concern. Table S3. Reinfections. Table S4. Significant associations of baseline variables with differential antibody rate of change. Fig. S1. Overall distribution of antibody responses for each isotype and antigen pair of the 128 pre-pandemic samples (negative controls) along with the cutoffs.