This picture shows a tarp with words and handprints in yellow paint in US treatment unit for Liberian healthcare workers infected with Ebola, during the site's decommissioning on April 30, 2015 in Monrovia. The US decommissioned the treatment centre on April 30, with Liberia set to be declared free of the virus within two weeks. Liberia is one of three countries, together with Guinea and Sierra Leone, that were ravaged by an epidemic that has killed around 11,000 people since December 2013, more than 500 of them healthcare workers. AFP PHOTO / ZOOM DOSSO (Photo credit should read ZOOM DOSSO/AFP/Getty Images)