- Life Cycle:
- "Humans become
infected by drinking unfiltered water
containing copepods (small crustaceans)
which are infected with larvae of D.
medinensis.
- Following
ingestion, the copepods are
killed and release the larvae,
which penetrate the host stomach
and intestinal wall and enter the
abdominal cavity and
retroperitoneal space.
- After maturation
into adults and copulation, the
male worms die and the females
(length: 70 cm to 120 cm) migrate
in the subcutaneous tissues
towards the skin surface.
- Approximately one
year after infection, the female
worm induces a blister on the
skin (generally on the distal
lower extremity), which ruptures.
- When this lesion
comes into contact with water (a
contact that the patient seeks to
relieve the local discomfort),
the female worm emerges and
releases larvae into the water.
- The larvae are
ingested by a copepod and after
two weeks (and two molts) have
developed into infective larvae.
Ingestion of the copepods closes
the cycle."
- Geographic
Distribution:
- "An ongoing
eradication campaign has dramatically
reduced the incidence of dracunculiasis,
which is now restricted to rural,
isolated areas in a narrow belt of
African countries and Yemen."
- courtesy of the Division of
Parasitic Diseases at the National Center for
Infectious Diseases, Centers for Disease Control
& Prevention
- http://www.dpd.cdc.gov/DPDx/HTML/Dracunculiasis.htm
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