UNITED NATIONS (AP):

The UN Ebola chief said yesterday it will take several more months before the outbreak in West Africa is under control.

An assessment that makes clear, the World Health Organisation's goal of isolating 100 percent of Ebola cases by January 1 will nott be met.

Dr David Nabarro said there has been "a massive shift" over the last four months in the way affected governments have taken the lead in responding to the epidemic. Communities are taking action and the international community has pitched in.

But he said greater efforts are needed to combat Ebola in western Sierra Leone and northern Mali to reduce the number of new cases in Liberia and to limit transmission to Mali.

WHO conceded that it did not meet the interim December 1 target of isolating 70 percent of Ebola patients and safely burying 70 percent of victims in hardest-hit Sierra Leone.

It has not been clarified what that means for its January 1 goal, which it set in September. It has acknowledged that its patchy data could compromise the goal, since the agency does not know how many Ebola patients there actually are, and is unable to track all of their contacts.

UN Secretary-General Ban Ki-moon said last month, the outbreak might not be contained until sometime next year.

"We must be prepared for ups and downs, difficulties and successes," Nabarro said in a meeting promoting greater collaboration between the UN and the business community, in responding to Ebola.

"It's going to take, I'm afraid, several more months before we can truly declare that the outbreak is coming under control."

More than 18,100 people have been infected and more than 6,500 have died in West Africa, since the initial case in Guinea, at an area bordering Sierra Leone and Liberia, a year ago.

Unlike previous Ebola outbreaks, which had been confined to faraway villages in the rain forests of Central Africa, this one quickly spread to capital cities in all three West African nations, and has become the worst in history.