A parasitic disease that infected 3.5 million people annually in 1986 claimed just ten victims worldwide in 2025. The Carter Center announced in April 2026 that dracunculiasis, commonly known as Guinea worm disease, has reached its lowest recorded level in history. If the transmission chain is completely severed, it will become only the second human disease ever eradicated.
A disease that causes almost unimaginable suffering
The Guinea worm (Dracunculus medinensis) is a roundworm whose larvae live inside tiny crustaceans found in drinking water. Anyone who swallows contaminated water ingests the larvae. Inside the body, the worm grows for months, sometimes reaching a meter in length, before pushing through the skin, usually at the legs and feet. This process takes weeks and causes extreme pain. There is no drug. There is no vaccine.
In 1986, when the Carter Center launched its global eradication campaign under former US President Jimmy Carter, an estimated 3.5 million people in 20 countries suffered from the disease. The World Health Organization had not even listed dracunculiasis as a notifiable illness at that point.
The strategy: behavior change, not chemistry
Because neither vaccine nor cure exists, the eradication strategy rests entirely on behavior change: filtering drinking water through fine-mesh cloth, isolating infected individuals to prevent them from contaminating water sources, and systematically educating communities about transmission routes. Village-level volunteers were trained, surveillance networks built, and every reported case investigated by field workers on the ground.
The result is a decline of more than 99.9 percent over four decades. The ten remaining human cases in 2025 were spread across three countries: four in Chad, four in Ethiopia and two in South Sudan. More than 200 countries have already received WHO certification as Guinea worm-free.
A historic benchmark
The only disease ever completely eliminated from humanity is smallpox, declared eradicated in 1980 after a worldwide vaccination campaign. Guinea worm disease would be the second, with a crucial distinction: smallpox was defeated by a vaccine. Dracunculiasis is being fought without any pharmaceutical weapon, through behavior change and relentless surveillance alone.
The journal Nature called this remarkable in 2024: even without a drug or diagnostic tool, eradication is within reach. The US Centers for Disease Control and Prevention describes the campaign as one of the most sustained efforts in international public health history, one that had to work in the poorest regions of the world without any technological shortcut.
The remaining hurdle: animal reservoirs
What makes eradication harder than with smallpox is a biological problem: Guinea worms also infect animals, primarily dogs, but also baboons, frogs and lizards. In Chad, more infected dogs than infected humans have been found in recent years, suggesting animals serve as a reservoir that sustains transmission to people. The Carter Center has introduced reward programs for reported animal cases and is researching methods to combat the parasite in animal reservoirs.
These animal infection chains are not yet fully understood scientifically. Chad, the country with the most animal cases, remains the biggest remaining challenge on the path to complete eradication.
What comes next
For official WHO certification, a country must demonstrate at least three consecutive years of zero human cases while maintaining an intensive surveillance system. Even if no further transmission occurs in 2026, the certification process will still take several more years. The Carter Center and WHO have announced they will maintain and intensify monitoring in Chad, Ethiopia and South Sudan until complete eradication is confirmed.
Ten cases from a starting point of 3.5 million: what remains is statistically almost nothing. Among specialists, complete eradication is considered a matter of time, not of feasibility.