Figure 7.

Value of the ${\mathcal{R}}_0$ index, as defined in (6), as a function of time, according to (9), in the four cases, from left to right: $\kappa =0$, κ as in (20), 10κ and 20κ. The effect of quarantine is evident: increasing values of κ result in longer periods where ${\mathcal{R}}_0$ exceeds one, but with lower values of the index. This typically results in a more bearable stress on the health system