Dracunculiasis (Guinea Worm Disease): A Report

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