Dracunculiasis Guinea Worm Disease. Dracunculiasis Commonly as the Guinea worm disease Commonly as...
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Transcript of Dracunculiasis Guinea Worm Disease. Dracunculiasis Commonly as the Guinea worm disease Commonly as...
DracunculiasisDracunculiasis Commonly as the Guinea worm diseaseCommonly as the Guinea worm disease Causes by the largest of tissue parasites Causes by the largest of tissue parasites
affecting humans, the parasitic round affecting humans, the parasitic round worm worm Dracunculus medinensisDracunculus medinensis
Transmitted to people when they drink Transmitted to people when they drink water containing copepods that are water containing copepods that are infected with infected with Dracunculus medinensisDracunculus medinensis
Rarely fatal but often incapacitating for Rarely fatal but often incapacitating for several monthsseveral months
Not currently possible to drugs prevent Not currently possible to drugs prevent or treat withor treat with
Historical:Historical:
Thought to be referred Thought to be referred to in a book written in to in a book written in Egypt 3,500 years ago Egypt 3,500 years ago (the Ebers' Papyrus). (the Ebers' Papyrus).
Probably the "fiery Probably the "fiery serpent" referred to in serpent" referred to in the Bible. the Bible.
Also may be the coiled Also may be the coiled serpents on the serpents on the "Caduceus" the symbol "Caduceus" the symbol of a physician. of a physician.
Dracunculus medinensisDracunculus medinensis
EpidemiologyEpidemiology . In 1986, there were an estimated . In 1986, there were an estimated
3.5 million cases of Guinea worm in 20 3.5 million cases of Guinea worm in 20 endemic nations in Asia and Africa.endemic nations in Asia and Africa. The The number of cases has been reduced by more number of cases has been reduced by more than 99% to 3,190 in 2009, 3,185 of them in than 99% to 3,190 in 2009, 3,185 of them in the four remaining endemic nations of the four remaining endemic nations of Africa: Sudan, Ghana, Mali and Ethiopia. Africa: Sudan, Ghana, Mali and Ethiopia.
Life Cycle Life Cycle
Adult females in subcutaneous tissues of the Adult females in subcutaneous tissues of the legs and arms. legs and arms.
Blister forms over nematode. Breaks when Blister forms over nematode. Breaks when exposed to water. exposed to water.
Nematode uterus ruptures and discharges first Nematode uterus ruptures and discharges first stage juveniles into the water (ovoviviparous). stage juveniles into the water (ovoviviparous).
Juveniles ingested by copepod (intermediate Juveniles ingested by copepod (intermediate host, 2 molts within copepod). host, 2 molts within copepod).
Copepod swallowed by human. Copepod swallowed by human. Juveniles migrate via lymph system. Juveniles migrate via lymph system. Develop to adults in subcutaneous tissues. Develop to adults in subcutaneous tissues.
MorphologMorphology y
Dracunculus medinensis is usually Dracunculus medinensis is usually
whitewhite
The adult female is among the The adult female is among the
longest nematodeslongest nematodes
Often measures one meter in lengthOften measures one meter in length
No more than 1-2 mm wide (thin like No more than 1-2 mm wide (thin like
spaghetti)spaghetti)
The male is generally much smaller The male is generally much smaller
and raerly recovered from humans and raerly recovered from humans
because he dies shortly afer matingbecause he dies shortly afer mating
Symptoms/Symptoms/Pathogenicity Pathogenicity None until blister forms and toxic fluids None until blister forms and toxic fluids
result in - result in - – a rash accompanied by severe itching a rash accompanied by severe itching – nausea nausea – vomiting vomiting – diarrhea diarrhea – dizziness. dizziness.
Secondary bacterial infections of opening Secondary bacterial infections of opening are possible. are possible.
There may be later symptoms--fibrosis of There may be later symptoms--fibrosis of the skin, muscles, tendons and joints ( may the skin, muscles, tendons and joints ( may interfere with locomotion or use of limbs). interfere with locomotion or use of limbs).
SymptomsSymptoms On occasion worms migrate to On occasion worms migrate to
joints , die prematurely, & calcifyjoints , die prematurely, & calcify The calcified worms can trigger The calcified worms can trigger
arthritis, locked joints, or permanent arthritis, locked joints, or permanent crippling & deformitiescrippling & deformities
DiagnosisDiagnosis
Made by observing visible Made by observing visible characteristics of the disease & characteristics of the disease & communicating with the infected communicating with the infected personperson
Possible to discover infection up to Possible to discover infection up to six months befor emergence six months befor emergence
Enzyme-linked Enzyme-linked immunoelectrotransfer Blot (EITB)immunoelectrotransfer Blot (EITB)
Treatment Treatment There is no cure. The only treatment is to remove the There is no cure. The only treatment is to remove the
worm over many weeks by winding it around a small stick worm over many weeks by winding it around a small stick
and pulling it out a tiny bit at a time. Sometimes the and pulling it out a tiny bit at a time. Sometimes the
worm can be pulled out completely within a few days, but worm can be pulled out completely within a few days, but
the process usually takes weeks or months.the process usually takes weeks or months.
No medication is available to end or prevent infection. No medication is available to end or prevent infection.
However, the worm can be surgically removed before the However, the worm can be surgically removed before the
wound begins to swell. Antihistamines and antibiotics can wound begins to swell. Antihistamines and antibiotics can
reduce swelling and ease removal of the wormreduce swelling and ease removal of the worm
Prevention Prevention To stop the infection of the Guinea worm you To stop the infection of the Guinea worm you
must keep Guinea worm larvae out of the must keep Guinea worm larvae out of the drinking water. Use only water that has been drinking water. Use only water that has been filtered or obtained from a safe source.filtered or obtained from a safe source.
Water can be boiled, filtered through tightly Water can be boiled, filtered through tightly woven nylon cloth, or treated with a larvae-woven nylon cloth, or treated with a larvae-killing chemical. People with an open Guinea killing chemical. People with an open Guinea worm wound should not enter ponds or wells worm wound should not enter ponds or wells used for drinking water.used for drinking water.