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 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

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

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. Historical Highlights

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

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

The Lifecycle

First-stage larvae (L 1 ) are released into water by a mature female worm L 1 remain active in the water up to 1 week until they are ingested by a suitable copepod The transformation to infectious third stage larvae (L 3 ) occurs within 2 weeks

The Lifecycle Infection of man is effected when swallowing infected copepods After 3 month the worms mate and the male dies. The female continues to grow and travel down the muscle planes. The female emerges after months to release larvae in water and completes the cycle…

Morphology

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 Male Female

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 lower the 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

Symptoms

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

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

Diagnosis

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

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

Treatment

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

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 dont display a statistically significant reduction in worm burden when 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 isnt acquired (re-infections are possible)

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

Prevention

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 water used for drinking Education, education, education !

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 people with drinking water

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

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

Current Impact Dracunculiasis is currently limited to remote, rural villages in 13 sub-Saharan African countries without access to safe drinking water The vast majority of current cases inflict citizens of the war-torn nation of Sudan

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.

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

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%

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

Thank You Shelly Beard Nicole Corder Majken Kiyohara