Fig. 10.

SARS-CoV-2 transmission constrained by government stringency index. (a) individual variation in susceptibility to infection; (b) individual variation in exposure to infection; (c) assuming homogeneity. Modelled trajectories of COVID-19 deaths (black) and cumulative percentage infected (blue). Green dots are data for daily reported deaths. Basic reproduction numbers modified by the stringency index (Hale et al., 2020) (${\mathcal{R}}_{\mathrm{c}}$) displayed in shallow panels underneath the main plots. Input parameters: progression from $\mathsf{E}$ to $\mathsf{I}$ ($\delta =1/5.5$ per day); recovery ($\gamma =1/4$ per day); relative infectiousness between $\mathsf{E}$ and $\mathsf{I}$ stages ($\rho =0.5$); and IFR ($\varphi =0.9\%$). Initial basic reproduction numbers, coefficients of variation and control parameters estimated by Bayesian inference (estimates in Table 4). Fitted curves represent best fitting trajectories and shades are 95% credible intervals generated from $10,000$ posterior samples.