The long-term absence of onchocerciasis in an area where the vectors, Simulium spp., are found.
D000818:Animals; D004175:Diptera / Q000502:physiology*; D005247:Feeding Behavior; D005260:Female; D006166:Guatemala; D006801:Humans; D008297:Male; D009855:Onchocerciasis / Q000453:epidemiology*