JARWENG, South Sudan — Noble Prize-winning peacemaker Jimmy Carter spent nearly four decades waging war to eliminate an ancient parasite plaguing the world’s poorest people.

The former president changed global health by sparing millions of people from Guinea worm, river blindness and other preventable diseases.

On a 2007 visit to Savelugu Hospital in Ghana, President Jimmy Carter asks a group of children if they've had Guinea worm. A raised hand is a yes.

Since the re-emergence of guinea worm in a remote village in South Sudan, the Carter Center has returned to raise awareness about what Guinea worm looks like, distribute water filters and train people on how to use them.

In 1986, international health experts decided to eliminate the Guinea worm disease. The campaign was led by the Carter Center, founded by former President Jimmy Carter.