Fig. 4: FcR binding at convalescent timepoints is higher in children than adults.

Spike specific antibodies that bind to FcγRIIa (A–C) and FcγRIIIa (D–F) in infected children (red) and adults (black) (A, D) over time shown as individual values with predictions from a generalised additive mixed model and 95% CI and at (BCEF) convalescent ( > 14 days post infection) timepoints (n = 53 children and 71 adults in (B), 34 children and 71 adults in (C), and 111 (E) or 110 (F) children and 82 adults in (E, F)). 12 (B, E) or 10 (E, F) non-infected children and 10 non-infected adults were tested in (B, C, E, F). Responses shown with bars for mean ± SD and as (B, E) raw FcR binding responses and (C, F) ratio of FcR response to total IgG. Lower bars are not shown if at 0 or below. Groups were compared with two-sided Kruskal-Wallis with Dunn’s multiple comparisons. A, D Longitudinal responses are plotted up to 138 days and represent 75 samples from 52 children and 105 samples from 79 adults (A) or up to 180 days with 231 samples from 137 children and 122 samples from 85 adults (D). The GAMMs account for participants’ IDs as random effect and age group as fixed effects (A, D). The p-values correspond to the significance of age group as a parametric coefficient in the model and the average increase of response in children compared to adults is indicated. 95% confidence intervals are depicted by the shaded areas (A, D). Source data are provided as a Source Data file.