Fig. 9.

Plots of two solutions to Eqs. (1) with different possibilities for the effect of the social distancing measures introduced by the lockdown of Mar. 9. In both panels, the full lines show, for comparison, what would be the solutions if the epidemic remained uncontrolled, whereas the dashed lines in corresponding colors show the effect of social distancing measures beginning at $t=14$. The results on the left panel were produced with ${ϵ}_1=0.566$, $\xi =0.04$, and those on the right panel were obtained with ${ϵ}_1=0.52$, $\xi =0.5$. The remaining parameters are the optimal ones determined using the results presented in Fig. 6. The choice for the left panel is an example of what we called an optimistic choice. The right panel corresponds to a pessimistic choice for the parameters. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)