Guinea Worm Disease (Dracunculiasis): What It Is, Why It Happens, and How It's Treated
Updated: 3 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Quick Answer
Guinea worm disease (dracunculiasis) is spread by drinking stagnant water containing copepods infected with worm larvae. There are usually no symptoms for about a year while the worm grows up to 3 feet long, then it exits through a painful blister. No drug exists; the worm is pulled out slowly over days to weeks. Safe drinking water prevents it. [1] [2]
What the research says
Human cases have fallen by more than 99%. Between 1986 and 2023, yearly human cases dropped from an estimated 3.5 million to 14. In 2024, 15 human cases and 664 animal infections were reported, and as of June 2025 transmission was still occurring in six African countries. (Hopkins et al., MMWR, 2026)
Eradication is close, but animal infections are the last-mile obstacle. A 2026 review reported only 10 human cases worldwide in 2025, the lowest total on record, achieved without a vaccine, curative drug or rapid diagnostic test. Persistent infections in dogs, civil conflict and funding gaps threaten the final steps. (Davis et al., Trop Med Infect Dis, 2026)
Animals now act as a reservoir. Cases fell from an estimated 3.5 million a year in 1986 to 13 human cases in 2022, but since 2012 infections have also appeared in dogs, then in cats and baboons. The program has set a 2030 target for eradication certification. (Delea et al., Am J Trop Med Hyg, 2024)
What Is Guinea Worm Disease?
Guinea worm disease, medically called dracunculiasis, is a parasitic infection caused by the worm Dracunculus medinensis. It is found mainly where clean drinking water is hard to get. Infection begins when a person drinks stagnant water that contains microscopic crustaceans called copepods, often called water fleas, which carry the worm's larvae. People and animals can also be infected by eating aquatic animals, such as fish or frogs, that have swallowed infected copepods. [1]
Inside the body, the larvae pass through the wall of the stomach or intestine and mature into adult worms. Females can reach up to 3 feet (1 meter) in length. About a year after infection, the adult female moves to the surface of the skin, most often on the lower leg or foot, and emerges to release larvae back into water. [1] [2]
Feature | Details |
Scientific name | Dracunculus medinensis |
Common name | Guinea worm disease or dracunculiasis |
Main source | Stagnant ponds or shallow wells |
Carrier | Copepods (water fleas) |
Global status | Close to eradication; as of June 2025 found in six African countries |
Symptoms and the Emergence Process
For the first year after infection there are usually no symptoms. [2] The first sign is typically a painful blister, usually on the foot or leg, that forms as the adult worm prepares to exit.
The Emergence Phase
As the worm pushes through the skin it causes intense pain, swelling and blistering, and emergence can take several weeks. Around this time, people may also have:
Fever and nausea
Vomiting and wheezing
Itching and eye swelling
Joint pain
The pain is often disabling, so people may be unable to walk or work for weeks to months. It often strikes during peak farming seasons, when labour is most needed. [3]
Causes and Complications
The root cause is drinking water contaminated with infected copepods. The disease does not spread directly from person to person. The larvae must pass through water fleas first. When an emerging worm touches water, it releases larvae that infect new water fleas, which completes the cycle.
Potential Complications
The main risk is the open wound the worm leaves, which can develop a secondary bacterial infection. [1] Inflammation caused by the worm can also damage joints and may lead to lasting disability. [2]
Diagnosis and Treatment Options
Providers diagnose Guinea worm disease by seeing the worm emerge from the skin. There are no tests that can detect the infection during the year before the worm appears. [2]
How the Worm Is Removed
There is no drug to treat Guinea worm infection and no vaccine to prevent it. [1] Care focuses on removing the worm and managing symptoms:
Manual extraction: A provider winds the emerging worm around a small stick and turns it a little each day, pulling out only a small amount at a time. It can take several weeks for the worm to leave the body completely. [2]
Surgical removal: Sometimes a provider removes the worm surgically. [2]
Supportive care: Pain relievers and steroids may be prescribed, and antibiotics are needed only if a bacterial infection develops. [2]
Prevention and Eradication Efforts
Because the parasite relies on stagnant water, Guinea worm disease is preventable with safe water practices. Public health programs focus on safe water, filtering drinking water, treating water sources to kill water fleas, and community education. [3] The Guinea Worm Eradication Program has been led by The Carter Center since 1986, with CDC, WHO and UNICEF. (Hopkins et al., MMWR, 2026)
How to Protect Yourself
If you live in or travel to an area where Guinea worm disease occurs:
Conclusion and Next Steps
Guinea worm disease is painful and disabling, and it shows how much access to clean water matters. The world is close to eradicating this parasite, but vigilance, funding and control of animal infections remain essential in affected regions.
Looking for clear answers on tough health questions? Browse plain-language health guides at Rinnit.com.
Frequently Asked Questions
What is Guinea worm disease?
It is a parasitic infection caused by the worm Dracunculus medinensis. People mainly get it by drinking water that contains water fleas (copepods) carrying the worm's larvae.
How do you get Guinea worm?
By drinking stagnant water from ponds or shallow wells that contain infected copepods. People and animals can also be infected by eating aquatic animals, such as fish or frogs, that have swallowed infected copepods.
What are the symptoms of Guinea worm?
About a year after infection, a painful blister forms, usually on the leg or foot, followed by the emergence of the worm. Fever, nausea, vomiting, itching, eye swelling, wheezing and joint pain can occur around that time.
Can Guinea worm be cured with medicine?
No. There is no drug to treat the infection and no vaccine to prevent it. The worm is removed slowly and carefully, and medicines treat pain, inflammation or infection of the wound.
How long does it take for the worm to come out?
It can take several weeks for the worm to leave the body completely. Only a little can be pulled out each day.
How long can a Guinea worm grow?
Adult female worms can grow up to 3 feet (1 meter) long.
Where is Guinea worm disease found?
As of June 2025, transmission was still occurring in six African countries: Angola, Cameroon, Chad, Ethiopia, Mali and South Sudan.
How many people get Guinea worm today?
Very few. Human cases fell from an estimated 3.5 million in 1986 to 14 in 2023 and 15 in 2024, and a 2026 review reported 10 human cases in 2025, the lowest total on record.
Is Guinea worm contagious?
No. It does not spread from person to person. It spreads only through contaminated water or undercooked aquatic animals that carry infected water fleas.
Can animals get Guinea worm?
Yes. Since 2012, infections have been found in dogs, and later in cats and baboons. In 2024, 664 animal infections were reported, including 299 in dogs in Cameroon and 234 in Chad.
What is the "stick method" for removal?
It is the traditional way to remove the worm. A provider wraps the emerging worm around a stick and turns it a little each day to pull out a few centimeters at a time.
How is Guinea worm diagnosed?
By seeing the worm emerge from the skin. No tests can diagnose the infection before then.
What happens if the wound gets infected?
The open wound can develop a secondary bacterial infection. A provider may prescribe antibiotics, and keeping the wound clean is important.
How is the disease being eradicated?
Through safe drinking water, filtering water, treating water sources to kill water fleas, finding and containing every case, community education and, more recently, controlling infections in animals.
Is Guinea worm fatal?
It usually is not fatal, but secondary infections of the wound can be dangerous and the pain can be disabling.
Related Reading
Parasites: Types, Symptoms, and Prevention Strategies explains the main types of parasites and how to avoid them.
Loiasis (African Eye Worm): Causes, Symptoms, and Treatment covers another tropical worm that travels under the skin.
Cellulitis: Symptoms, Causes, Diagnosis and Treatment — What You Need to Know explains the skin infection that can develop around an open wound.
Tetanus (Lockjaw): Symptoms, Causes, Treatment, and Vaccination Guide explains tetanus, a wound infection that vaccines can prevent.
References
Centers for Disease Control and Prevention. About Guinea Worm. CDC. March 14, 2024. https://www.cdc.gov/guinea-worm/about/index.html
Cleveland Clinic. Guinea Worm Disease (Dracunculiasis). Cleveland Clinic. August 11, 2025. https://my.clevelandclinic.org/health/diseases/guinea-worm-disease
World Health Organization. Dracunculiasis (Guinea-worm disease). World Health Organization. November 4, 2019. https://www.who.int/news-room/questions-and-answers/item/dracunculiasis-(guinea-worm-disease)
Hopkins DR, et al. Progress Toward Eradication of Dracunculiasis (Guinea Worm Disease) - Worldwide, January 2024-June 2025. MMWR Morb Mortal Wkly Rep. 2026;74(42):648-654. PMID 41468347. https://doi.org/10.15585/mmwr.mm7442a2
Davis BR, et al. Guinea Worm Eradication: New Clinical and Public Health Challenges at the Last Mile. Trop Med Infect Dis. 2026;11(8). PMID 42646795. https://doi.org/10.3390/tropicalmed11080218
Delea MG, et al. Slaying the Serpent: A Research Agenda to Expand Intervention Development and Accelerate Guinea Worm Eradication Efforts. Am J Trop Med Hyg. 2024;111(3_Suppl):12-25. PMID 38981490. https://doi.org/10.4269/ajtmh.23-0889
Medical disclaimer
This article is for general educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified healthcare provider with any questions you may have about a medical condition. Never disregard professional medical advice or delay seeking care because of something you have read here. If you think you may have a medical emergency, call your doctor or emergency services immediately.
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