Figure 1

Anti-Receptor binding domain (RBD) total antibodies (in log10 in BAU/mL) in plasma from elderly nursing home residents. A antibody levels prior to and after one (pre-3D and post-3D, respectively) or two (pre-4D and post-4D, respectively) COVID-19 vaccine booster doses. B Antibody levels in vaccinated/SARS-CoV-2-experienced (Vac-ex) and vaccinated/SARS-CoV-2-naïve subjects (Vac-n) at the different sampling times. The number of plasma samples available for analyses at the different sampling times is shown. Bars indicate medians and IQRs. P values for differences are shown.