FILE In this Monday, Jan. 19, 2015 file photo, a health care worker, right, takes the temperatures of school children for signs of the Ebola virus before they enter their school in the city of Conakry, Guinea. The World Health Organization says it wi
FILE In this Monday, Jan. 19, 2015 file photo, a health care worker, right, takes the temperatures of school children for signs of the Ebola virus before they enter their school in the city of Conakry, Guinea. The World Health Organization says it wi

The last known Ebola patient in Guinea, a 21-day-old baby girl, has recovered at a treatment center in the capital, Conakry, potentially signaling the end of the worst Ebola outbreak in history.

Dozens of people in Guinea are still being monitored to see whether they develop symptoms of the virus. But if no other cases are found in the next 42 days, Guinea will be declared Ebola-free, nearly two years after the epidemic began.

The incubation period for Ebola is 21 days and, out of an abundance of caution, twice that period of time must pass before the World Health Organization declares the disease is defeated in Guinea.

"It suddenly looks like we really could be at an end before Christmas," said Margaret Harris, a spokeswoman for the WHO.

Two neighboring countries also ravaged by the Ebola epidemic, Liberia and Sierra Leone, have already been declared Ebola-free.

The epidemic, which began in Guinea, has killed more than 11,000 people in West Africa.