U.S. funding for medical research by source, 1994-2012. (Data were adjusted to 2012 dollars using the Biomedical Research and Development Price Index.) American Medical Association hide caption

itoggle caption American Medical Association

This experimental Ebola vaccine, developed by the U.S. government, is just one of several undergoing small-scale, preliminary testing. University of Maryland School of Medicine/AP hide caption

itoggle caption University of Maryland School of Medicine/AP

Dr. Bruce Ribner, medical director of Emory University Hospital's infectious disease unit, embraces Dr. Kent Brantly (left) who was treated with an experimental Ebola medicine and released from the Atlanta hospital Thursday. John Bazemore/AP hide caption

itoggle caption John Bazemore/AP