Cohort characteristics. (a) WHO score subject distribution of 3–8 by severity category: mild 3–4, moderate 5–6, and severe 7–8. (b) Donors age distribution for all samples used in the study, separated by healthy control and WHO severity groups. (c) The days since symptom onset, relative to sample collection timepoint. Boxplots were produced using the default settings in R. In all boxplots (Figure 1B and C), the bottom and top of the box are and (25th and 75th percentiles), and the black line near the middle of the box is (median, 50th percentile). The height of the box is the interquartile range (). The lower and upper whiskers are determined according to the following equations: Where is the variable being plotted.