Visitors from the International Aid Organizations, the U.S. State Department and Department of Defense tour a mock-up of an Ebola treatment unit built to train health care workers as part of Operation United Assistance in Paynesville, Liberia, Dec. 3, 2014. United Assistance is a Department of Defense operation to provide command and control, logistics, training and engineering support to U.S. Agency for International Development-led efforts to contain the Ebola virus outbreak in West African nations. (U.S. Army photo by Sgt. 1st Class Brien Vorhees, 55th Signal Company (Combat Camera)/Released)