Dracunculiasis (guinea-worm disease) is a parasitic disease caused by Dracunculus medinensis that is a long, thread-like worm. Dracunculiasis is commonly known as guinea-worm disease (GW). It is transmitted exclusively when people drink stagnant water contaminated with parasite-infected water fleas (Cyclops- that carry infective guinea-worm larvae).
Dracunculiasis is rarely fatal, but infected people become crippled, non-functional for weeks. It affects people in rural, deprived and isolated communities who depend mainly on open surface water sources such as ponds for drinking water.
An estimated 3.5 million cases of dracunculiasis occurred during the mid-1980s in 21 countries worldwide, 17 countries of which were in Africa. The number of reported cases fell to only 22 cases globally in 2015 (lowest number of cases so far) compared with 126 cases in 2014. In 2015, cases were reported from four endemic countries – Chad (9), Mali (5), South Sudan (5) and Ethiopia (3). World Health Organization (WHO) has certified 198 countries, territories and areas (belonging to 186 Member States) as free of dracunculiasis.
People do not usually have symptoms until about one year after they become infected with parasite.
- Person may develop fever, swelling, and pain in the area from where worm/ worms come out. In 90% cases site is usually lower legs and feet.
- The adult female worm comes out of the skin as whitish filament; it can be very painful, slow, and disabling period (duration of emergence: 1 to 3 weeks).
- The pain may get worse if the wound develops a secondary bacterial infection.
- Dracunculiasis is a parasitic disease caused by Dracunculus medinensis, a long, thread-like worm.
- The transmission cycle (from the time infection occurs until a mature worm emerges from the body) takes about 10–14 months to complete .
- During the emergence of worm from the body, a painful blister develops mostly on the lower legs and feet. One or more worms may emerge from the body accompanied by burning pain.
- To relieve the burning pain patients often immerse the infected part of the body in water. The worm(s) then releases thousands of larvae (baby worms) into the water.
- These larvae are ingested by tiny crustaceans or copepods, also called water fleas and mature in to the infective stage.
- People when drinking contaminated water also swallow the infected water fleas. The water fleas are killed in the stomach and the larvae are liberated. These larvae penetrate the wall of the intestine and migrate through the body.
- The fertilized female worm (which measures from 60–100 cm long) migrates under the skin tissues until it reaches its exit point, usually at the lower limbs.
- A blister or swelling is formed at exit point from which parasite emerges.
- Clinical presentation of guinea –worm disease is so typical and well known to local people in endemic areas that it is sufficient to make diagnosis.
- Examination of the fluid discharged by the worm can show rhabditiform larvae.
- No serologic test is available.
There is no drug to treat Guinea worm disease and nor any vaccine to prevent infection.
Once part of the worm begins to come out of the wound, the rest of the worm can only be pulled out, a few centimeters each day by winding it around a piece of gauze or a small stick. This process usually takes several weeks.
Local cleansing of the lesion and local application of antibiotics will prevent secondary infection.
The worm can also be surgically removed by a doctor before an ulcer forms.
There is no drug to treat Guinea- worm disease and nor any vaccine to prevent infection. However prevention is possible through preventive strategies.
It is through preventive strategies that the disease is on the verge of eradication globally. Prevention strategies include:
- Guinea worm case detection with the continuous surveillance.
- Preventing transmission from each worm by treatment, cleaning and bandaging regularly the affected skin-area until the worm is completely expelled from the body.
- Making drinking water safe: provision and maintenance of safe drinking water supply on priority in GW endemic villages.
- Preventing drinking water contamination by advising the patient to avoid wading into water by :
- Not allowing villagers, especially those with blisters and ulcers, to enter any source of drinking water.
- Converting step wells to draw wells.
- Controlling of Cyclops:
- By use of temephos
- Filtering water of open water bodies before drinking in endemic areas through fine mesh (size 100 micrometers), or double layered cloth strainers to remove Cyclops.
- Increasing awareness among endemic communities by health promotion and behavior change.