A microscope image of the Ebola virus is seen on a television news report inside the U.S. Centers for Disease Control and Prevention's Emergency Operations Center, Tuesday, Aug. 5, 2014, in Atlanta. An American aid worker infected with Ebola arrived Tuesday from Liberia to Emory University Hospital, just downhill from the CDC, joining a second patient being given an experimental treatment that has never before been tested on humans. (AP Photo/David Goldman)
