A Liberian doctor infected with Ebola who received one of the last doses of an experimental drug has died. Two American missionaries recovered after getting the same drug; a Spanish priest who received it also died. The World Health Organization said Monday an unprecedented proportion of healthcare workers have been infected in the West African outbreak due to factors including a lack of equipment and dire staff shortages. More than 240 healthcare workers have contracted Ebola, and more than 120 have died.