1 / 35

Dracunculiasis (Guinea Worm Disease): A Report

Dracunculiasis (Guinea Worm Disease): A Report. Shelly Beard, Nicole Corder, and Majken Kiyohara . Dracunculiasis – In Brief:. Commonly known as the guinea worm disease Caused by the largest of tissue parasites affecting humans, the parasitic roundworm Dracunculus medinensis

randi
Download Presentation

Dracunculiasis (Guinea Worm Disease): A Report

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Dracunculiasis(Guinea Worm Disease):A Report Shelly Beard, Nicole Corder, and Majken Kiyohara

  2. Dracunculiasis – In Brief: • Commonly known as the guinea worm disease • Caused by the largest of tissue parasites affecting humans, the parasitic roundworm Dracunculus medinensis • Transmitted to people when they drink water containing copepods that are infected with Dracunculus medinensis larvae • Rarely fatal but often incapacitating for several months • Not currently possible to prevent or treat with drugs

  3. The Report: • Historical highlights • The lifecycle • Morphology • Symptoms • Diagnosis • Treatment • Prevention • Socioeconomic impact, past and present • The eradication initiative

  4. Historical Highlights Old Testament: 021:006 And the LORD sent fiery serpents among the people, and they bit the people; and much people of Israel died. 021:007 Therefore the people came to Moses, and said, We have sinned, for we have spoken against the LORD, and against thee; pray unto the LORD, that he take away the serpents from us. And Moses prayed for the people. 021:008 And the LORD said unto Moses, Make thee a fiery serpent, and set it upon a pole: and it shall come to pass, that every one that is bitten, when he looketh upon it, shall live.

  5. Historical Highlights: • The 'fiery serpent' mentioned in the Old Testament • The serpents coiled around the staff of Hermes, the symbol of a physician • Believed to be anything from exposed nerves to dead tissue in the Middle Ages • It was suggested that they were worms in mid 1700s • 1905: The life cycle was described • 1986: Dracunculiasis was chosen as the next disease to be targeted for worldwide eradication

  6. Classification Dracunculus medinensis: • Nematode (also known as roundworms) • Superfamily: Dracunculoidea • Order: Spirurida • Mammalian tissue parasites • Eggs or larvae require arthropods (insects or crustaceans) as intermediate hosts

  7. The Lifecycle

  8. The Lifecycle First-stage larvae (L1) are released into water by a mature female worm Œ L1 remain active in the water up to 1 week until they are ingested by a suitable copepod  The transformation to infectious third stage larvae (L3) occurs within 2 weeks Ž

  9. The Lifecycle Infection of man is effected when swallowing infected copepods  Œ Œ After 3 month the worms mate and the male dies. The female continues to grow and travel down the muscle planes.   Ž The female emergesafter 10-14 months to release larvae in waterand completes the cycle…

  10. Morphology

  11. Female Male Morphology • Dracunculus medinensis is usually white • The adult female is among the longest of nematodes: • Often measures one meter in length • No more than 1-2 mm wide(thin like spaghetti or angel hair pasta) • The male is generally much smaller and rarely recovered from humans, because he dies shortly after mating

  12. Techniques used to evade the Human Immune System: • Roundworms have an outer protective cuticle layer; some worms can even survive in pure vinegar • Opiates from Dracunculus medinensis lowerthe sensation of pain in the human host and significantly decrease the immune systems’ responsiveness • Antigen cloaking, disguises itself as human • Manipulate the humans' immune system to prevent acquisition of immunity

  13. Symptoms

  14. Symptoms: • Most often asymptomatic from time of infection until days before emergence • Pre-partum Immune response: • Fever, ulceration, and a painful burning sensation in the area where the worm will present • Post-partum susceptibility to secondary infections in open wounds

  15. Symptoms: • On occasion worms migrate to joints, die prematurely, and calcify. • The calcified worms can trigger arthritis, locked joints, or permanent crippling and deformities

  16. Diagnosis

  17. Patent Diagnosis • Made by observing visible characteristics of the disease and communicating with the infected person

  18. Prepatent Diagnosis • Desirable in an effort to achieve containment of the disease • Possible to discover infection up to six months before emergence • Falcon Assay Screening Test-Enzyme-Linked Immunosorbent Assay (FAST-ELISA) • Enzyme-linked Immunoelectrotransfer Blot (EITB) technique • However, testing is complex, expensive and not well suited for the socioeconomically challenged areas where Dracunculiasis still occurs

  19. Treatment

  20. Traditional Treatment • Traditional treatment starts when the worm begins to emerge from the body • The worm is wrapped around a small stick in order to prevent retraction and facilitate the extraction which can take weeks • For the ones fortunate enough to afford it: • An analgesic can be taken to reduce the swelling associated with the blister • Antibiotic ointment and proper cleansing can be used to prevent secondary bacterial infections

  21. Medications • The medications generally used for parasitic worm infections do not work to eliminate Dracunculus medinensis: • Treatment with drugs such as diethylcarbamazine, albendazole, and invermectin don’t display a statistically significant reduction in worm burdenwhen compared with controls • Mebendazole usage increased the chance of the worm emerging in locations other than the feet and legs • Vaccines are currently not available, and immunity isn’t acquired (re-infections are possible)

  22. Invasive Treatment • Surgical removal of the worm (before a blister forms) shortens the duration of the debilitating pain and prevents further contamination of water sources • However, this form of treatment is rarely desirable or even an option in socioeconomically challenged areas

  23. Prevention

  24. Prevention • Lack of treatment options and the burden of care during the long infectious process brings the focus to prevention • Preventative measures: • Treating contaminated water sources with larvicide • Providing drinking water from underground sources • Filtering to remove copepods from surface waterused for drinking • Education, education, education !

  25. Challenges • Cultural and religious practices • Chemicals should not be added to sacred ponds • Fear of “filtering off the power” of sacred water • Belief that Dracunculiasis is a result of witchcraft • Getting to all the rural locations with occurrences • Social unrest, such as ongoing war in Sudan This pond serves 1,500 peoplewith drinking water

  26. Socioeconomic Impact

  27. Socioeconomic Impact • It has been estimated that infected people lose 100 days of work per year • Children are absent from school for 25% of the school year, if they or members of their family are infected • The cost in lost revenue for the individual and the community can be very high

  28. Historical Impact • Written and pictorial documents indicate that Dracunculus medinensis has affected mankind for many centuries • The titles “Guinea” and “Medina” stem from areas with significant incidences of the disease • A finding of a male worm in a mummy indicates that the wealthy were also susceptible to infection

  29. Current Impact • Dracunculiasis is currently limited to remote, rural villages in 13 sub-Saharan African countries without access to safe drinking water • The vast majorityof current casesinflict citizens ofthe war-torn nationof Sudan

  30. Distribution by Country of 10,674 Cases of Dracunculiasis, 2005 – Includes imported cases • The last known indigenous case occurred in Kenya in 1994, but this country has been kept in the stage of pre-certification of eradication because of annual importations of cases from Sudan.

  31. Dracunculiasis in the USA? A case history from 1995: • Nine year old emigrant from Sudan. Before leaving Sudan, a Dracunculus medinensis worm was extracted successfully from her right leg • After arriving in the United States another worm began to emerge from her left leg • She presented to a clinic in Tennessee with a secondary infection; treatment with antibiotics was unsuccessful • Surgical intervention facilitated removal of the fragmented worm, pus, and necrotic tissue • With proper outpatient therapy, the girl was able to walk and returned to normal

  32. The Eradication Initiative

  33. The Eradication Initiative • In the 1980s a global campaign was launched to eradicate Dracunculiasis worldwide • At that time Dracunculiasis was known to inflict India, Pakistan, 16 sub-Saharan countries in Africa, as well as Yemen • Eradication efforts began in 1982 in India and shortly thereafter in Pakistan, Ghana, Nigeria, and Cameroon • By 1995, all of the known endemic countries established eradication programs • Between 1980 and now, the cases worldwide have been reduced by more than 99.5%

  34. Pakistan: An Example of Eradication • Village-wide search for cases of Dracunculiasis in 1987 • Reached 47,401 of the 50,000 suspected endemic villages • The main interventions: monofilament nylon or polyester cloth filters, and chemical treatment of drinking water sources with temephos • Trained healthcare workers in villages to identify and report cases of Dracunculiasis • Case containment began in 1990 • Incentive rewards were offered in 1991 to any health worker or individual reporting a case of Dracunculiasis in a village • Pakistan has been free from Dracunculiasis since 1994

  35. Thank You Shelly Beard Nicole Corder Majken Kiyohara

More Related