Fig. 4

Variation of yellow fever spillover intensity in space and time. Plots of variance of the predicted spillover intensity throughout the 13-year time series from the National model (a), low reservoir richness Regional model (b), and high reservoir richness Regional model (c). Darker municipalities are predicted to have greater seasonality in spillover risk than lighter municipalities. The seasonal pattern in model predictions are shown by monthly averages of predicted spillover intensity across the entire study area of Brazil for the National model (d), within the low reservoir richness Regional model (e), and within high reservoir richness Regional model (f). Gray lines represent an individual year of data with overall mean in black. Rug along x-axis represents true spillover events, with larger and darker shapes representing more spillover events during that calendar month. Map projection: SAD69 Brazil Polyconic. Data source: 2001 municipality boundaries, Brazilian Institute of Geography and Statistics