FILE - In this Sept. 30, 2014 file photo, nine-year-old Nowa Paye is taken to an ambulance after showing signs of the Ebola virus disease in the village of Freeman Reserve, about 48 kilometers (30 miles) north of Monrovia, Liberia. The World Health Organization said on Tuesday, April 28, 2015 that it aims to identify all new Ebola cases in West Africa by the end of May to stop the spread of the lethal virus before the rainy season. (AP Photo/Jerome Delay, File) The Associated Press