Jacquelyn Martin, Associated Press
President Barack Obama pauses while speaking about the Ebola outbreak response by the U.S. in West Africa, Wednesday, Feb. 11, 2015, in the South Court Auditorium of the White House complex in Washington. Obama plans to withdraw most US military troops fighting Ebola outbreak in West Africa.

WASHINGTON — As the Ebola outbreak in West Africa abates, President Barack Obama is withdrawing nearly all the U.S. troops sent to Liberia in September when the disease threatened to spiral out of control.

Obama planned to announce Wednesday that only 100 of the 2,800 troops would remain after April 30, for emergency assistance purposes. About 1,500 have returned home. Those staying will work with Liberia's military, regional partners and U.S. civilians.

Before the president's announcement, he met privately with Ebola responders from the United States.

"Just 10 months since the first U.S. government personnel deployed, we have delivered extraordinary results," said Rajiv Shah, head of the U.S. Agency for International Development. He said cases were down 80 percent and that in Liberia, there were just one or two new ones per day.

The U.S. pullout comes as Ron Klain, who led Obama's Ebola response, wraps up his short-term assignment.

J. Stephen Morrison, senior vice president and director of the Global Health Policy Center at the Center for Strategic and International Studies, said that without the boost from the U.S. and British militaries in the region, "we would have faced a complete runaway outbreak and a complete unraveling of society which was well on its way."

Obama faced initial criticism over his administration's response, particularly after health workers contracted the virus at a Texas hospital while treating a patient that had been infected in Africa. The U.S. tightened policies at home and dedicated more resources to West Africa.

At the height of the outbreak, Liberia was experiencing 119 confirmed Ebola cases per week.

Still, U.S. officials and independent experts worry about recent increase in cases in Guinea, and an inability to further reduce case counts in Sierra Leone.

"What we're seeing in Guinea and in Sierra Leone is that the new cases are not cases that are showing up on known contacts lists," said Morrison, who worked at USAID and the State Department during the Clinton administration.

While careful not to declare the crisis over, the White House promoting the decline in Ebola cases as a sign that U.S. and global efforts had paid off.

Officials said the U.S. helped build 15 Ebola treatment units, trained more than 1,500 health workers and coaxed the world community into contributing more than $2 billion to Ebola efforts.

The outbreak has killed more than 9,100 people, and the World Health Organization has warned it will be challenging to bring cases to zero. The outbreak is expected to cost the three most-affected countries — Liberia, Sierra Leone and Guinea — at least $1.6 billion in lost economic growth.

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