Fig. 1: Map of Bioko Island, Equatorial Guinea, showing enumeration areas (EAs) selected for the difference in differences analysis.

EAs in teal are those in the top quartile of historical smoothed travel prevalence. EAs in gold are those in the bottom quartile of historical smoothed travel prevalence. EAs in gray were not selected for the analysis. EAs outlined in orange and filled with patterned dots are the areas with known land use changes over the study period.