Figure 4. Projected Zika virus dynamics and transmission potential.

(A) Fitted and projected epidemic attack rate (% population infected, or herd-immunity, green), basic reproduction number ($R_0$, red) and effective reproduction number ($R_e$, blue).(B) Colourmap showing the projected total number of annual cases depending on rate of external introduction of infectious individuals.The black arrow in the color scale marks the total number of real cases necessary for 1 notified case to be reported in FSA. (C) Projected incidence dynamics when considering less than 1 (green), 2 (blue) and 12 (red) external introductions per year. Grey and white shaded areas delineate different years. The Y-axes are normalised to 1 in each subplot for visualisation purposes. In (B, C) results are based on 1000 stochastic simulations with parameters sampled from the posterior distributions (Figure 3). Representative model solutions for incidence, R0 and Re from 500 MCMC chain samples are available in Supplementary files 1–6 (both deterministic and stochastic).