The Viral Insurgent: Ebola in Sierra Leone: Muller_Ebola_SierraLeone_02

Doctors Without Borders medical staff discuss patient status across an established safety cordon in an Ebola treatment center in Kailahun, Sierra Leone on Sunday, August 17, 2014. Those in masks stand in the {quote}high risk{quote} zone where highly contagious Ebola victims receive treatment. (Pete Muller/Prime for the Washington Post)

Doctors Without Borders medical staff discuss patient status across an established safety cordon in an Ebola treatment center in Kailahun, Sierra Leone on Sunday, August 17, 2014. Those in masks stand in the "high risk" zone where highly contagious Ebola victims receive treatment. (Pete Muller/Prime for the Washington Post)