The Ebola virus outbreak in West Africa has killed at least 3,091 people out of the 6,574 infected so far, the World Health Organization reported Friday. The death toll is nearly double that of all other Ebola outbreaks in history combined.

The virus has killed more than 1,830 people in Liberia, which has seen a sharp increase in fatalities in since midsummer, while Guinea has made gains in containing the disease. More than 150 people died in the last two days.

The United Nations has a $1 billion working goal of funding for its recently announced U.N. Mission for Ebola Emergency Response, or UNMEER, which will deploy on the ground to fight the disease. UNMEER will be based in Accra, Ghana, and will deploy in the capitals of Sierra Leone, Liberia and Guinea throughout next week. The International Monetary Fund approved $130 million in funding to fight the outbreak on Friday.

President Barack Obama opened the U.N. high-level meeting with an impassioned call for a “fast and sustained” response.

"That’s only possible if every nation and every organization does its part," he said. "And everyone has to do more.”

The WHO said Friday it’s investigating if convalescent therapies, or blood and plasma transfusions from survivors of the virus to those fighting it, are a viable large-scale treatment option. Convalescent therapy appeared to help American missionary doctor Kent Brantly recover from the disease. The treatment is promising and relatively inexpensive compared to extremely scarce vaccine and drug treatments currently available.