Contributor: Gordon K. Klintworth
Dracunuliasis is a helminth disease produced by Dracunculus medinensis. This nematode is endemic in South America, South Asia as well as in West and East Africa. Humans are a natural host and the female worm migrates to the skin and elicits blisters that burst on contact with water. Fist stage larvae are liberated from the ruptured blisters and they become ingested by crustaceans (Cyclops sp.) in which they undergo further development. After drinking contaminated water humans become infected. The postgravid adult nematode dies and may calcify. Mature worms occasionally migrate to the conjunctiva and eyelids. Periorbital edema sometimes develops as part of a generalized hypersensitivity reaction. A granulomatous reaction forms around the worm and this is often followed by suppuration. A foreign body giant cell reaction forms around the dead and often calcified adult worm. Dracunculus medinesis sometimes produces lesions in the eyelid.