Neighbourhood map showing the geographical distribution of S. mansoni egg counts before treatment (Figure 2a). Also shown in Figure 2a are the lines partitioning the study area into four sectors (A, B, C and D) as described in the text. Box and whisker plots of egg counts stratified by these sectors are shown in Figure 2b. The horizontal lines in each box correspond to the median values, the lower edge of the box is the 25%ile, the upper edge of the box is the 75%ile. The whiskers represent the range of data beyond these percentiles, excluding outliers.