Sierra Leone, one of the three worst Ebola-stricken West African countries, has managed to curb the Ebola outbreak, World Health Organization (WHO) and United Nation’s officials say.

"Sierra Leone is in much better shape today to control Ebola than it was a few weeks ago," said the United Nations Special Representative and Head of the United Nations Mission for Ebola Emergency Response (UNMEER), Ismail Ould Cheikh Ahmed, in the country’s capital, Freetown, on Friday.

Ahmed also said, "From everything I've seen so far, I am optimistic that Sierra Leone can get by," adding further progress requires "considerable effort by all".

Pujehun District in the Southern Province of Sierra Leone has become the first in the country with a record of 42 days with no registered cases of Ebola. The number of days is twice the incubation period of the virus.

The considerable progress was mainly due to increased number of beds available and burial teams, said the WHO's Assistant Director-General Bruce Aylward, adding the new resources need to be used effectively.

"There are signs that case incidence may have leveled off in Sierra Leone, although with 248 new confirmed cases reported in the week to 4 January 2015, it remains by far the worst-affected country at present," the WHO said.

The Ebola epidemic has taken 8,235 lives out of 20,747 known cases worldwide over the past year, the WHO said in its update released on Wednesday, January 7, 2015.

Sierra Leone, Liberia and Guinea, are three worst hit countries to which the majority of the cases have been ascribed.

Ebola is a form of hemorrhagic fever, whose symptoms are diarrhea, vomiting, and bleeding. The virus spreads through direct contact with infected blood, feces, or sweat. It can also spread through sexual contact or the unprotected handling of contaminated corpses.