Fig. 2: MenACWY-specific serum bactericidal activity (rSBA) and ps-specific IgG and IgM responses following primary MenACWY-TT vaccination.

MenACWY-specific rSBA responses A and corresponding percentages of participants with rSBA titers ≥8 and ≥128 (B), ps-specific IgG (C) and IgM (D) concentrations were determined pre-vaccination (pre-), at one month (1 m) and one year (1 y) post-primary MenACWY-TT vaccination for all participants (n = 222). At two years (2 y) post-primary vaccination, responses were assessed only in participants who did not receive a booster vaccination at 1 y (n = 110). Geometric mean titers (GMTs) and geometric mean concentrations (GMCs) are indicated in black, with error bars representing the 95% confidence intervals. Following log10-transformation, rSBA and antibody responses were compared between timepoints using paired generalized linear mixed models (GLMM), followed by post-hoc Emmeans tests and subsequent Bonferroni correction for multiple testing. Proportions of participants with rSBA ≥8 or ≥128 (with 95% CI) were calculated with the Wilson score interval with continuity correction.