In an update, the United Nations health agency said 4,941 people had died of confirmed, suspected or probable cases of Ebola in the three West African countries that have been worst hit by the outbreak.

A total of 13,540 confirmed, probable or suspected cases have been reported in Guinea, Liberia, and Sierra Leone, the WHO said, with all districts in Liberia and Sierra Leone reporting at least one case of Ebola since the epidemic began.

Earlier Friday the WHO opened a new treatment unit at the former Ministry of Defense compound in the outskirts of the Liberian capital Monrovia. The new unit adds another 200 beds to the almost 500 currently available for Ebola patients in the city.

Five other countries, including Nigeria and the U.S., have reported an additional 27 cases and 10 more deaths since the outbreak began, the WHO said. The total number of cases reported was fewer than reported this past week due to some suspected cases in Guinea being discarded.