Fig. 5.

Endemic incidence (Model 2) as a function of: A. The reproduction number ($R_{\mathrm{NPI}}$) and duration of immunity ($D$). B. $R_{\mathrm{NPI}}$ and vaccine efficacy ($v_e$). C. Importation rate ($f$) and $R_{\mathrm{NPI}}$. D. $f$ and $v_e$. E. $D$ and $v_e$. F. $D$ and $f$. We set baseline parameter values such that vaccine induced immunity and immunity due to infection last for 2 years, and boosters are given 4 months after immunity wanes. Parameter values are: $f=3$ cases per 100k per day, vaccination rate $\nu =0.7\text{\%}$ per day, $D=2$ years, $v_e=$ 80%, and $R_{\mathrm{NPI}}=3$. In each subplot three parameters are varied at the same time: the two parameters declared in the subplot title and the parameter presented in the horizontal axis of the subplot, while the remaining two parameters are fixed with their values declared in the subplot title. Numbers are not adjusted for ascertainment. These results are from pre-Omicron model predictions.