Health ministers from 11 African countries are meeting in the Ghanaian capital, Accra, to plan "drastic action" against the worst Ebola outbreak in history as dozens of new cases continue to emerge.
There have been 759 confirmed or suspected cases of the haemorrhagic fever in Guinea, Liberia and Sierra Leone, the World Health Organisation says, with 467 people known to have died as of Wednesday.
The new death toll represented a rise of 129 - or 38 percent - since the UN agency's last update given just a week ago.
"This makes the ongoing Ebola outbreak the largest in terms of the number of cases and deaths as well as geographical spread," WHO said in a statement announcing a two-day conference in Accra.
The UN reassured West African nations on Wednesday that the world's deadliest-ever Ebola epidemic could be stopped in its tracks, telling the region's health ministers: "We can handle this."
"This is not a unique situation - we have faced it many times - so I'm quite confident that we can handle this," Keiji Fukuda, assistant director-general for health security at the WHO, said.
"This is, however, the most complicated Ebola outbreak ever because it is spreading so fast in both urban and rural areas."
WHO has described the current Ebola epidemic as one of the most challenging since the virus was first identified in 1976 in what is now Democratic Republic of Congo.
Meanwhile, the Red Cross in Guinea said on Wednesday it had been forced to suspend operations tackling Ebola in the country's southeast after staff there were threatened by a group of men armed with knives.
The incident on Tuesday in Gueckedou, about 650km southeast of the capital Conakry, is the latest in a series against health workers, undermining efforts to help the region's weak health systems fight one of the world's deadliest diseases.
Medical charity Doctors Without Borders (MSF) said last week that the spread of the virus, which has had a mortality rate of up to 90 percent in previous outbreaks, was "out of control", with more than 60 outbreak hotspots.
On Tuesday, Liberian authorities have warned that anyone caught hiding suspected Ebola patients will be prosecuted.
Some families, faith healers and traditional doctors were reported to be removing patients from hospital for special prayers and traditional medicine.
The outbreak of the deadly disease is already the largest and deadliest so far, according to the WHO.