Fig. 1: Interventions reduce peak infection prevalence.
a–f Time courses of epidemics under optimal (a), fixed control (b), and full suppression (c) interventions with three different values of intervention duration τ—14 days (dark lines), 28 days (intermediate lines), and 56 days (light lines)—and their respective intervention functions b(t) (d–f). At time t, the basic reproduction number \({{\mathcal{R}}}_{0}\) is reduced to some fraction of its maximum (no intervention) value; b(t) gives that fraction. Dashed black line shows time course in the absence of intervention. g, h Effect of the duration τ on the peak infectious prevalence (g) and the intervention starting time (h) for the optimal intervention (green), the optimized fixed control intervention (blue), and the optimized full suppression intervention (red). Dotted red line shows the critical value τcrit below which full suppression is the globally optimal intervention. Plotted parameters: \({{\mathcal{R}}}_{0}=3\) and \(\gamma =\frac{1}{14}\) days−1. See Table 1 for parameter justifications.
