Dracunculiasis, or guinea worm disease, is a parasitic disease caused by the nematode Dracunculiasis medinensis. It is limited to mostly remote rural communities that do not have access to safe drinking water. It is transmitted by contaminated drinking water containing water fleas that are infected with D. medinensis larvae. In infected individuals, the worm emerges as a whitish filament in the center of a painful ulcer of the lower extremity, impairing mobility for up to several weeks.