Your Guide to
Neglected Tropical Diseases

Dracunculiasis, also known as Guinea worm disease, is a parasitic infection acquired by drinking contaminated water. When a person consumes water containing microscopic infected water fleas, the larvae are released inside the body. Over the course of about one year, the larvae grow into adult worms. The female worm can reach up to 3 feet in length. When the worm is ready to release its larvae, it creates an intensely painful blister on the skin, usually on the leg or foot. Over several weeks, the worm slowly emerges from the wound--a process that is extremely painful and disables people for weeks or even months.

Many people cannot work, attend school, or care for their families during this time. Secondary bacterial infections from the wound can make the condition worse. While rarely fatal, the disease causes severe suffering and economic hardship. No medicine or vaccine exists.

Guinea worm disease spreads through contaminated water sources. When someone with an emerging worm enters water to relieve the pain, the worm releases larvae into the water. Tiny water fleas in ponds and stagnant water swallow these larvae. When people drink unfiltered water from these sources, they swallow the infected water fleas. Once inside the body, the larvae are released and grow into adult worms over the course of about a year.

People can also get infected by eating raw fish or frogs that have swallowed infected water fleas. The disease mainly affects people in rural areas who rely on ponds and other stagnant water for drinking. Dogs and other animals are also susceptible to Guinea worm infections, making eradication more challenging.

Geographic scope:

• In the 1980s, the disease was found in about 20 countries across Africa and Asia.
• Today, active transmission has been reduced to just 6 countries: Angola, Cameroon, Chad, Ethiopia, Mali, and South Sudan. Only Chad, Ethiopia, and South Sudan reported human cases in 2025.
• WHO has certified 200 countries as free of Guinea worm disease.

Population affected:

• In 1986, there were about 3.5 million cases per year; that year, the Guinea Worm Eradication Program was launched.
• By 2025, human cases dropped to just 10 (mostly in Chad and South Sudan), representing a 99.99% reduction.
• Animal infections (mostly in dogs) remain a challenge: approximately 650 animal infections were reported in 2024.
• Goal: complete eradication by 2030, which would make Guinea worm disease the second human disease eradicated after smallpox.

There is no available medicine or vaccine. Once the worm starts emerging, it must be slowly wound around a stick, a few centimeters each day, over several weeks. Pulling too quickly can break the worm and cause serious complications. Pain relievers and antibiotic ointments help manage symptoms and prevent infections. People do not develop immunity and can get infected again. Since 1986, the Guinea Worm Eradication Program has worked to eliminate the disease through prevention strategies. The main approaches include filtering all drinking water through cloth or pipe filters, using safe water sources like wells instead of ponds, and keeping infected people away from water sources. Communities watch for cases and detect them quickly.

Infected people can stay at treatment centers where they receive care and food until the worm is removed. Some countries offer cash rewards for reporting cases. For infected animals, programs focus on finding and containing them, educating owners, and controlling water sources. These efforts have reduced cases by 99.99% and brought the disease to the verge of eradication.