Abbas Dulleh, Associated Press
In this Tuesday, Nov. 25, 2014 file photo, Liberian President Ellen Johnson Sirleaf, center, has her temperature taken by a Chinese soldier, left, before the opening of a new Ebola virus clinic sponsored by China, in Monrovia, Liberia. Liberia’s president says the country must and will get to zero Ebola cases. President Ellen Johnson Sirleaf made the comment Wednesday, Feb. 11, 2015, while appearing at an Armed Forces Day celebration.

MONROVIA, Liberia — Liberia's president vowed Wednesday that the country would get to zero Ebola cases soon as the U.S. military announced it will be withdrawing most of its troops who have spent the last several months helping to battle the disease.

Only 100 U.S. troops will remain in West Africa after April 30, down from 2,800 initially deployed. Those staying in West Africa will work with Liberia's military, regional partners and U.S. civilians to continue fighting Ebola.

Liberian President Ellen Johnson Sirleaf noted the significant gains, as the country had just four confirmed cases a week ago. It's a dramatic reduction from August and September, when some 300 cases a week were being registered.

"We must remain vigilant and determined as we always have been," the 76-year-old president said at an Armed Forces Day program Wednesday that also was attended by top U.S. military officials in Liberia.

More than 3,800 people have died from Ebola in Liberia over the past year, with a total toll of more than 9,100 across Liberia, Guinea and Sierra Leone.

On Tuesday, Guinea's president traveled to Sierra Leone for a visit focused on the remaining challenges in battling the Ebola outbreak. The presidents are urging airlines to re-establish services that were cut at the height of the crisis last year.

While careful not to declare the crisis over, the White House has touted declining Ebola cases as a sign that U.S. and global efforts are paying 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.

Associated Press writer Josh Lederman in Washington contributed to this report.