Transcript Dracunculus medinesis: The Most Cunning Parasite from an

Dracunculus medinesis:
The Most Cunning Parasite from an
Immunological Perspective
By: Tiffany Walsh
November 10, 2005
Dracunculus medinensis
Phylum: NEMATODA
CLASS: SECERNENTEA
ORDER: SPIRURIDA
FAMILY: DRACUNCULIDAE
Dracunculus medinensis
Common name: Guinea worm,
medina worm, serpent worm
Historical:
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Thought to be referred to in a
book written in Egypt 3,500
years ago (the Ebers'
Papyrus).
 Probably the "fiery serpent"
referred to in the Bible.
 Also may be the coiled
serpents on the "Caduceus"
the symbol of a physician.
Dracunculus medinensis
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Hosts: Humans
Distribution: Asia, Africa, Indonesia, Fiji,
Brazil
– Mostly in Sudan as of 2004.
Map-2002
What do they LOOK like?
Life Cycle
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Adult females in subcutaneous tissues of the legs
and arms.
Blister forms over nematode. Breaks when
exposed to water.
Nematode uterus ruptures and discharges first
stage juveniles into the water (ovoviviparous).
Juveniles ingested by copepod (intermediate
host, 2 molts within copepod).
Copepod swallowed by human.
Juveniles migrate via lymph system.
Develop to adults in subcutaneous tissues.
Symptoms/Pathogenicity
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None until blister forms and toxic fluids result in 
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a rash accompanied by severe itching
nausea
vomiting
diarrhea
dizziness.
Secondary bacterial infections of opening are possible.
There may be later symptoms--fibrosis of the skin,
muscles, tendons and joints ( may interfere with
locomotion or use of limbs).
Future Management
• Filter or boil water, or treat with chlorine
to kill intermediate host.
• Avoid bathing or wading in drinking water.
• Remove worms by extraction or with
surgery.
• Drug therapy.
• Video