The United States has announced plans to send at least fifty public health and epidemics experts to West Africa to help in the desperate effort to contain the worst-ever outbreak of Ebola. Senior U.S. and European health officials said the outbreak is now out of control, but insisted it could still be stopped. The Ebola outbreak has so far claimed more than 700 lives in Guinea, Liberia, Sierra Leone, and Nigeria. The current mortality rate is about 55 percent.