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What is dracunculiasis?

Dracunculiasis, more commonly known as Guinea worm disease, is a preventable infection caused by the parasite Dracunculus medinensis. Infection affects poor communities in remote parts of Africa that do not have safe water to drink.

Currently, many organizations, including The Global 2000 program of The Carter Center of Emory University, UNICEF, Centers for Disease Control and Prevention (CDC), and the World Health Organization (WHO) are the last 13 countries in the world (all in Africa) to eradicate the disease. Since 1986, when an estimated 3.5 million people were infected, the campaign has eliminated much of the disease.

In 1998, only 78,338 cases of Guinea worm were reported. Most of those cases were from Sudan where the ongoing civil war makes it impossible to eradicate the disease. All affected countries except Sudan are aiming to eliminate Guinea worm disease by the year 2000.

How does infection occur?

People get infected with Guinea worm disease by drinking water contaminated with Dracunculus larvae. In the water, the larvae are swallowed by small copepods "water fleas." The worms mature inside the water flea and become infective in about 10 days. Once the worms have matured inside the water flea, any person who swallows contaminated water becomes infected.

Once inside the body, the stomach acid digests the water flea, but not the Guinea worm. For the next year, the Guinea worm then grows to full size adult. Adult worms can grow up to 3 feet long and are as wide as a spaghetti noodle.

After a year, the worm will migrate to the surface of the body. As the worm migrates, a blister develops on the skin where the worm will emerge. This blister will eventually rupture, causing a very painful burning sensation. For relief, persons will immerse the affected skin into water. The temperature change causes the blister to erupt, exposing the worm. When someone with a Guinea worm ulcer enters the water, the adult female emerges from the wound and releases a milky white liquid containing millions of immature worms into the water, thus contaminating the water supply. For several days after it has emerged from the ulcer, the female Guinea worm releases more immature worms when it comes in contact with water.

What are the signs and symptoms of Guinea worm disease?

Infected persons do not usually have symptoms until about 1 year after they drink water contaminated with Dracunculus-infected water fleas. A few days to hours before the worm emerges, the person may develop a fever, swelling, and pain in the area. More than 90% of the worms appear on the legs and feet, but may occur anywhere on the body.

People, in remote, rural communities who are most commonly affected by Guinea worm disease do not have access to medical care. Therefore, ulcers may take many weeks (8 weeks average) to heal; often becoming infected with bacteria. This causes disabling complications, such as locked joints or even permanent crippling. Each time a worm emerges, persons are often unable to work and resume daily activities for an average of 3 months. This usually occurs during planting or harvesting season, resulting in heavy crop losses. Parents who have active Guinea worm disease cannot care for their children. They also cannot tend or harvest or crops, which leads to financial problems for the entire family.

What is the treatment for Guinea worm disease?

Once the worm emerges from the wound, it can only be pulled out a few centimeters each day and wrapped around a small stick. Sometimes the worm can be pulled out completely within a few days, but this process usually takes weeks or months.

No medication is available to end or prevent infection. However, the worm can be surgically removed before an ulcer forms. Analgesics, such as aspirin or ibuprofen, can help reduce swelling; antibiotic ointment can help prevent bacterial infections.

Where is Guinea worm disease found?

Dracunculiasis now occurs only in 13 countries in Africa. Infected areas in Africa lie in a band between the Sahara and the equator. Most cases occur in poor rural villages that are not usually visited by tourists. More than half of all cases of Guinea worm are reported from southern Sudan. Other countries with more than a 1,000 cases annually are Nigeria, Ghana, Burkina Faso, Niger, Togo, and Ivory Coast. Smaller numbers of cases are reported from Uganda, Benin, Mali, Mauritania, Ethiopia, Chad.

Transmission of Guinea worm no longer occurs in several countries, including India, Pakistan, Kenya, Senegal, Yemen, and Cameroon. No locally acquired cases of disease have been reported in these countries in the last year or more.

Who is at risk?

Anyone who drinks standing pond water contaminated by persons with Guinea worm infection. People who live in villages where the infection is common are at greatest risk.

Is Guinea worm disease a serious illness?

Yes. The disease causes preventable suffering for infected persons and is a heavy economic burden for affected communities.

Is a person immune to Guinea worm disease once he or she has it?

No. Infection does not produce immunity, and many people in affected villages suffer disease year after year.

How can Guinea worm disease be prevented?

Because Guinea worm disease can only occur by drinking contaminated water, following these simple control measures can completely prevent illness and eliminate the disease.

  • Drink clean water, free from contamination.
  • Prevent persons with an open Guinea worm ulcer from entering ponds and wells used for drinking water.
  • Filter water fleas from drinking water.
  • Treat contaminated water sources with a chemical, such as Abate*, that kills water fleas.


* Use of trade names is for identification only and does not imply endorsement by the Public Health Service or by the U.S. Department of Health and Human Services.


This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you may have a parasitic infection, consult a health care provider.

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