Mali has eliminated Guinea worm disease bringing the world a step closer to eradicating the debilitating parasitic disease that is now only endemic in three African countries, the U.S.-based Carter Center said, citing provisional government figures.

Guinea worm afflicted 3.5 million people 30 years ago but is now only endemic in South Sudan, Chad and Ethiopia, where there were 16 reported cases last year, according to the organization set up by former U.S. president Jimmy Carter and his wife.

Last November, the doctor leading the fight against the disease which can cause worms up to a meter long to grow before emerging through the skin, said the world had never been so close to eradicating Guinea worm.