Figure 1

Distributions of pre-calibration ID50 (Panel A) and ID80 (Panel B) titers measured by the Duke and Monogram labs of convalescent patient samples, vaccine recipient samples, and the WHO International Standard sample. For the convalescent samples, the assay lower limit of detection (LLoD) is set at 20 for Duke and 40 for Monogram, the reciprocal of the starting dilution of each assay (these titers are also considered as the positivity cutoff values). For the vaccine samples collected at Day 29 and Day 57, 4 weeks post the first and the second Moderna doses, respectively, and the WHO I.S. sample, the assay LLoD is set at 10 for Duke and 40 for Monogram, the reciprocal of the starting dilution of each assay (these titers are also considered as the positivity cutoff values). Circle-shape points indicate titers > LLoD; triangle-shape points indicate titers ≤ LLoD.