Fig. 2.

Serological response to the first and the second dose of the BNT162b2 mRNA COVID-19 vaccine in individuals with and without laboratory-confirmed previous SARS-CoV-2 infection (y-axis is log-scaled ln(0.9 + ○) with raw values; whiskers mark mean and location of the 25/75 percentile/IQR) only a group with two doses of vaccine is presented, n = 62. After the first dose, in a group without previous SARS-CoV-2 infection 10 patients were still seronegative. The † symbol marks large effect in the Friedman test whereas corresponding p-values were obtained for the post hoc pairwise Wilcoxon test with Holm–Bonferroni adjustment; the ○ symbol marks large effect in ANOVA test whereas corresponding p-values were obtained for the post hoc pairwise t test with Holm–Bonferroni adjustment