Guinea Worm: Countdown to ZeroThe end of Guinea worm disease is within reach the result of a 25-year eradication campaign led by The Carter Center. In 1986, there were 3.5 million cases of Guinea worm in 21 countries in Africa and Asia. That number has now been reduced by more than 99 percent, with fewer than 1,100 cases remaining worldwide, concentrated primarily in South Sudan and Mali.