The number of deaths attributed to an epidemic of Ebola virus in Guinea, Liberia and Sierra Leone stood at 467 by Monday, out of 759 known cases in total, the World Health Organization said Tuesday.

The outbreak of the deadly disease is already the largest and deadliest ever, according to the WHO, which previously put the death toll at 399 as of June 23, out of 635 cases.

The 17 percent rise in deaths and 20 percent jump in cases in the space of a week will add urgency to an emergency meeting of 11 West African health ministers in Accra, Ghana set for Wednesday and Thursday, which aims to coordinate a regional response.

The WHO figures include confirmed, probable and suspected cases.

In response to the outbreak, Liberian authorities on Tuesday 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 in West Africa has left some of the world's poorest states, with porous borders and weak health systems undermined by war and misrule, grappling with one of the most lethal and contagious diseases on the planet.

The WHO said three key factors were contributing to the spread of the disease. One was the burial of victims in accordance with cultural practices and traditional beliefs in rural communities. Another was the dense population around the capital cities of Guinea and Liberia. The third was commercial and social activity along the borders of the three countries.

"Containment of this outbreak requires a strong response in the countries and especially along their shared border areas," the statement said.