Figure 1.

Required duration of mass drug administration (MDA) to bring microfilariae (mf) prevalence below the 1% critical threshold in treatment-naive settings, comparing the result from the 3 different models. The setting under consideration is specified in the caption of each subpanel, indicating the geographical region, recommended standard treatment regimen, and the precontrol mf prevalence considered. The current strategy (annual MDA with the recommended standard regimen at 65% coverage) is compared with alternative strategies differing in one aspect, including a switch to triple-drug regimen (ivermectin + diethylcarbamazine + albendazole; annual, 65% coverage), switch to biannual MDA (standard regimen, 65% coverage), or increased coverage of 80% (annual, standard regimen). Vertical line at t = 3 indicates the target year of elimination (ie, 2020, 3 years from the time of writing this paper). Error bars indicate the 90% prediction interval as calculated through bootstrapping. ^aSimulations for triple-drug scenarios were done with optimistic efficacy assumptions, as provided in Table 1. ^bImpact of increased coverage is shown for annual MDA, except for the “Africa ALB only” region, where it is shown for biannual MDA. Abbreviations: ALB, albendazole; cov., coverage; DEC, diethylcarbamazine; IVER, ivermectin; mf, microfilariae; PNG, Papua New Guinea; prev., prevalence.