WASHINGTON/GENEVA (Reuters) – The United States announced on Tuesday that it would send 3,000 troops to help tackle the Ebola outbreak as part of a ramped-up response including a major deployment in Liberia, the country where the epidemic is spiralling fastest out of control.The U.S. response to the crisis, to be formally unveiled later by President Barack Obama, includes plans to build 17 treatment centers, train thousands of healthcare workers and establish a military control center for coordination, U.S. officials told reporters. The World Health Organization has said it needs foreign medical teams with 500-600 experts as well as at least 10,000 local health workers, numbers that may rise if the number of cases increases, as it is widely expected to.