U.S. Marines and Sailors with SPMAGTF Crisis Response - Africa prepare to load bags of concrete onto an MV-22B Osprey to help local and international health organizations build Ebola Treatment Units while in support of Operation United Assistance in Monrovia, Liberia, Nov. 21, 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. Marine Corps photo by Lance Cpl. Andre Dakis/SPMAGTF-CR-AF Combat Camera/Released)