Fig. 2.

Nucleoprotein and Spike S1 IgG kinetics following COVID-19 vaccination. IgG measurements to Spike S1 (A) and Nucleoprotein (B) in infection-naïve individuals are shown over days since first vaccination. In (C) IgG measurements to Spike S1 are shown by prior exposure status and number of doses received, individuals were included if they were sampled ≥ 14 days after the first dose or ≥ 7 days after the second dose. In (A-C) the dashed horizontal line depicts the threshold for seropositivity. S1: Spike S1, N: Nucleoprotein, IgG: immunoglobulin G, BAU/ml: binding antibody units; NS: not significant (p > 0.05); *: p < 0.05; **: p < 0.01; ***: p < 0.001.