FILE - Former U.S. President Jimmy Carter poses for photographers with a water pipe filter, that is used to combat guinea worm disease, during a news conference to mark the launch of a campaign to eradicate the disease in central London, Wednesday, Oct. 5, 2011. (AP Photo/Lefteris Pitarakis, File)

FILE - In this Nov. 4, 2010 photo, Ajak Kuol Nyamchiek, 7, watches while John Lotiki, a nurse with the Carter Center, bandages the blister on her leg from where a guinea worm is slowly emerging in Abuyong, Sudan. (AP Photo/Maggie Fick, File)

FILE - In this March 9, 2007 file photo, a guinea worm is extracted by a health worker from a child's foot at a containment center in Savelugu, Ghana. (AP Photo/Olivier Asselin, File)

FILE - In this Nov. 4, 2010 photo, children collect drinking water from a pond using filters provided to them by The Carter Center's guinea worm eradication program in the remote village of Lengjak, in Awerial County, Lakes State, Southern Sudan. (AP Photo/Maggie Fick, File)

FILE - Former US President Jimmy Carter listens during a video interview with the Associated Press via a laptop at a hotel in London, Tuesday, Feb. 2, 2016. (AP Photo/Kirsty Wigglesworth, File)

FILE - Carter Center intern Sarah Ellis Peed helps assemble medical kits to fight Guinea worm disease at a warehouse in Atlanta, Wednesday, July 28, 2004. (AP Photo/John Bazemore, File)