Patterns of cross-reactivity of Z-EDIII (A) and ZED-I (B) antigens with longitudinal DENV samples. Intensities of serum binding in sandwich ELISAs for Z-EDIII and Z-EDI are shown as heat maps. Longitudinal samples (collected 14 to 23 days, 6 months, and 12 months postinfection) from patients with primary (left of the dashed line) or secondary (right of the dashed line) DENV3 infection were diluted 1:20, and the IgG antibodies bound to Z-EDI or Z-EDIII were measured using a sandwich ELISA. The resulting normalized OD values are represented by a color scale (green, lowest values; yellow, middle values; and red, highest values).