Ebola toll rises to more than 6,900: WHO

As of December 14, there were 18,569 cases of infection of the deadly virus in the three worst affected countries, Guinea, Liberia and Sierra Leone, and 6,900 deaths.

This is out of a total of 18,603 cases and 6,915 deaths across eight countries affected by the outbreak.

In some good news, the UN agency said Mali has not seen a new case for three weeks, completing one of the two 21-day incubation periods needed to be declared free of the virus.

The death toll in other countries was unchanged: six in Mali, one in the United States, and eight in Nigeria, which was declared Ebola free in October.

Spain and Senegal, which have both been declared free from Ebola, meanwhile counted one case each, but no deaths.

Sierra Leone earlier this month overtook Liberia as the country with the most infections.

But the WHO said: "There are signs the increase in incidence has slowed, and that incidence may no longer be increasing."

It counted 8,356 cases and 2,085 deaths up to December 14, up from 8,273 cases and 2,033 deaths a day earlier.

Liberia, long the hardest-hit country, has continued to see a decrease in the rate of transmission, the WHO said, although it had no new figures.

As of December 9, the country counted 7,797 cases and 3,290 deaths, up from the 7,765 infections and 3,222 deaths tallied two days earlier.

In Guinea, where the outbreak started nearly a year ago, 2,416 cases of Ebola and 1,525 deaths were recorded as of December 14, up from 2,394 cases and 1,518 deaths a day earlier.

The WHO said that incidence of infection was "fluctuating".

Ebola, one of the deadliest viruses known to man, is spread only through direct contact with the bodily fluids of an infected person showing symptoms such as fever or vomiting.

People caring for the sick or handling the bodies of people infected Ebola are especially exposed.