Fig. 1. Children have a significantly higher humoral response to SARS-CoV-2 than adults.

The humoral response generated following SARS-CoV-2 household exposure with seroconversion was examined using MULTICOV-AB. Children (orange, n = 181) produced significantly more antibodies against the Spike (a p = 6.00 x 10⁻⁶), Receptor Binding Domain (RBD) (b p = 2.86 x 10⁻⁶), S1 domain (c p = 3.00 x 10⁻¹⁴) and nucleocapsid (NC) (e p = 1.76 x 10⁻²) than adults (blue, n = 414). There was no significant difference for either the S2 domain (d p = 0.66) or the N-terminal domain of the nucleocapsid (NC NTD) (f p = 0.40). Only samples from T1 with a seropositive status (see Methods) are shown. Box and whisker plots with the box representing the median, 25th and 75th percentiles, while whiskers show the largest and smallest non-outlier values. Outliers were identified using upper/lower quartile ±1.5 times IQR. Statistical significance was calculated using Mann–Whitney-U (two-sided) with significance defined as being *<0.05, ***<0.001. Values >0.05 were defined as non-significant (ns). MFI Median Fluorescence Intensity.