A map showing global health issues under the surveillance at the U.S. Centers for Disease Control and Prevention is seen in the agency's Emergency Operations Center, Tuesday, Aug. 5, 2014, in Atlanta.... more 
A map showing global health issues under the surveillance at the U.S. Centers for Disease Control and Prevention is seen in the agency'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) less 
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Associated Press | Photo By David Goldman
Tue, Aug 5, 2014 6:48 PM EDT