Dracunculus (animal)

Dracunculus (animal)

D. alii
D. dahomensis
D. fuelliborni
D. globocephalus
D. insignis
D. lutrae
D. medinensis
D. ophidensis

Dracunculus is a genus of spiruroid nematode parasites in the family Dracunculidae. Some species infest humans, and alter their hosts’ behaviour in a way that supports the worm’s reproductive cycle. Dracunculus causes a blister to form on the host, often on the foot or lower leg, causing severe pain and a boiling sensation. This will cause the human host to dip the affected area in water to sooth the pain which will cause the blister to burst, allowing reproductive larvae into the water where they can await the next host to infect.

The worms can reach a metre in length. If one simply pulls off the protruding head of the worm, the worm will break and leak high levels of foreign antigen which can lead to anaphylactic shock and fast death of the host. Hence it is important to remove the worm slowly (over a period of weeks). This is typically undertaken by winding the worm onto a stick (say, a matchstick), by a few centimetres each day.