Figure 2.

Data used to estimate ecological and human population components of spillover (a–k) and estimates of overall spillover risk (l–o). Number of primate reservoir species (a), vector species probability of occurrence (b), reservoir–vector contact probability (c), human–vector contact probability (d), human susceptibility approximated by 1 minus estimated vaccine coverage (i), and human distribution (j) vary spatially. Vector seasonal abundance is modelled as a function of rainfall using mosquito capture data (e). Vector dispersal depends on distance and is estimated from mark–recapture studies (f). Vector survival has been measured at different temperatures in laboratory (open circles) and field (closed circles) settings and was used to estimate temperature-dependent vector lifespan (g). Transmission studies at different temperatures inform modelled probability of vector infectiousness as a function of days since infecting bite and temperature (h). Phenomenologically modelled reservoir disease prevalence (light blue line, k) is approximated from human case data (blue dots, k). All mechanistic model components (a–k) are derived from empirical data in previously published studies. Components a–h are used to predict environmental risk of disease spillover (l), components a–i are used for immunological risk (m), components a–j are used for population-scaled risk (n) and components a–h and k are used for periodic risk (o). The four disease risk metrics presented here for illustrative purposes were estimated for January 2001 (l–o). (Online version in colour.)