Titers over time. Mean titers are plotted against the superinfection interval for DENV2 (left) and DENV4 (right). Bars indicate standard errors of the mean (N = 4). Single-serotype infections are in black, mixed-serotype infection treatments are: coinfections (blue), superinfection of DENV4 after DENV2 (green), and superinfection of DENV2 after DENV4 (red). Treatment abbreviations correspond to the treatments described in Table 1.