Fig. 4.

Contour plot of $R_V$, as a function of vaccine efficacy (${\epsilon }_V$) and vaccination rate (${\psi }_V$) for the case where the average vaccine-induced immunity period is six month. Dark green line represents the value of ${\psi }_{Vbase}=\text{0.000 611}$, corresponding to a coverage $x_{coverage}=\text{0.2}$ and a time horizon $T=\text{365}$ days. Red lines show a scenario in which it is possible to reduce the $R_V$ value below one, considering a vaccine efficacy of 0.8 and a vaccination rate of 0.007.