Decision model of four strategies to reduce risk of L. loa encephalopathy following treatment with Mectizan® in areas that are 1) thought to be endemic for loiasis on the basis of remote sensing (the environmental risk model map); and 2) determined to be hyper- or meso-endemic for onchocerciasis by REMO. Abbreviations: oncho = onchocerciasis; Rx = treatment. Additional details on the model are available from the authors upon request. [+] indicates truncation of a branch to simplify the figure. For the remainder of this branch, see the structure of similarly labelled branches elsewhere in the figure.