Dracunculus medinensis
Everything you wanted to know about “Guinea Worms”
But, were afraid to askCrisAngel Presents
Guinea Worms and You
CDC estimates
• In 1986, there were 3.5 million cases worldwide• In 2009, there were fewer than 10,000 cases• Presently, there may be as few as 1,000 cases • Guinea worm disease is expected to be the next disease after smallpox to be eradicated
Classification/Taxonomy
Kingdom: Animalia
Phylum: Nematoda
Class: Secernentea
Order: Camallanida
Family: Dracunculidae
Genus: Dranunculus
Species: Meninensis
Geographic Distribution
• Predominantly in Africa. Also in India, Pakistan, Saudi Arabia, and Yemen
• Freshwater lakes and rivers
Who’s Your Host• Definitive host:
Humans, wolves, dogs, horses, cows, leopards, monkeys, and baboons (oh my!)
• Intermediate: Cyclops copepods
Morphology
• Female: 60 cm in length and can reach up to 3 ft• Male: much smaller 1.2-2.9 cm• Larvae: 500 and 700 micrometers
Humans are infected by drinking unfiltered water containing copepods that are infected with larvae. After ingestion, the copepods die and release the larvae. The larvae then penetrate the stomach and intestinal wall and enter the abdominal cavity and retroperitoneal space. The larvae mature and reproduce. The males die while the females migrate into the subcutaneous tissue toward the skin. After about one year of infection, the female worm induces a blister, which will rupture. When the blister comes into contact with water, the female worm emerges and releases larvae. Larvae are ingested by copepods and infective larvae are developed after about two weeks.
Life Cycle
Pathogenesis
• Emergent Worms• Severe pain, allergic
reactions, and blisters
• Secondary Bacterial Infections:• Caused by retreating
worms• Entry of tetanus spores
• Nonemergent Worms• Arthritis, cellulitis, and
necrosis
Complications• Cellulitis• Boils• Infection (sepsis)• Joint infection and
severe joint pain• Lock jaw• Disability
The Fiery Serpent
Symptoms• Slight Fever• Itchy Rash• Nausea• Vomiting • Diarrhea
Treatment1. Immerse foot2. Extract worm3. Bandage4. Drugs: None
Control:GWEP
1. Patient Surveillance2. Provide Safe Water3. Vector Control: Abate 4. Education
Works Cited
CDC: http://www.cdc.gov/parasites/guineaworm/prevent.html
CMR: http://cmr.asm.org/cgi/content/full/15/2/223/F4
Nature: http://www.nature.com/embor/journal/v10/n3/full/embor200919.html
NIH: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2536457/pdf/bullwho00088-0065.pdf WHO: http://www.who.int/dracunculiasis/disease/disease_more/en/index.html
Supplemental Videoshttp://reels.creativecow.net/film/foul-water-fiery-serpent
http://www.youtube.com/watch?v=Qwk-THcjmlI
http://www.youtube.com/watch?v=omudJzeX4q0&feature=fvst
http://www.youtube.com/watch?v=u4kQWvUv_Ns
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