infectious diseases
Dracunculiasis
Pathophysiology of Dracunculiasis
Humans become infected by drinking water containing infected microcrustaceans (copepods). The larvae are released, penetrate the bowel wall, and mature in the abdominal cavity into adult worms in about 1 year. After mating, the male dies, and the gravid female migrates through subcutaneous tissues, usually to the distal lower extremities. The cephalic end of the worm produces an indurated papule that vesiculates and eventually ulcerates. On contact with water (eg, when a person attempts to relieve the severe discomfort by immersing the affected limb), a loop of the worm’s uterus prolapses through the skin and discharges motile larvae. Worms that do not reach the skin die and disintegrate or become calcified. Larvae are ingested by copepods. In most endemic areas, transmission is seasonal and each infectious episode lasts about 1 year. 