Health ministers from 11 African countries are meeting in the Ghanaian capital, Accra, on Wednesday to plan "drastic action" against the worst Ebola outbreak in history as dozens of new cases continue to emerge.

The World Health Organization (WHO) says West Africa's Ebola outbreak has claimed 467 lives as the death toll continues to climb in all three countries where cases have been reported.

In a statement Tuesday it said 759 people have been infected in Guinea, Liberia and Sierra Leone.

The new numbers include suspected, probable and laboratory-confirmed cases. Their release comes on the eve of a two-day regional meeting in Ghana to improve efforts to combat the disease.

An update last week said there had been 367 deaths, already far higher than the previous most lethal outbreak, which killed 254 people in the Democratic Republic of Congo in 1995.

Transmission has been facilitated by widespread distrust of health workers, heavy traffic near the countries' porous borders and the spread of the disease to capital cities in both Liberia and Guinea, the WHO said.

The WHO has called for “drastic action” to combat the spread of the disease.

"This is no longer a country specific outbreak but a sub-regional crisis that requires firm action by governments and partners," Luis Sambo, WHO Regional Director for Africa, said in a statement last week. "WHO is gravely concerned by the on-going cross-border transmission into neighboring countries as well as the potential for further international spread," he said.

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 took place in Gueckedou, about 403 miles southeast of the capital Conakry.

A Medicins Sans Frontieres center in nearby Macenta was also attacked by youths two months ago after staff there were accused of bringing the disease to Guinea.

There is no vaccine and no known cure for Ebola, which initially induces fever, headaches, muscle pain and weakness. In its more acute phase, Ebola causes vomiting, diarrhea and external bleeding, symptoms that facilitate the rapid spread of the virus. Human-to-human contact, directly or via exposure to such secretions, is most often behind the transmission of the virus.

Al Jazeera and wire services