WHO expects more Ebola cases in Congo

At least 1500 people have been potentially exposed to the deadly Ebola virus in the Democratic Republic of Congo's North Kivu region, where insecurity prevents aid workers reaching some areas, the World Health Organisation says.

But it expects more people to become infected and cannot be sure it has identified all chains by which the virus is spreading in the eastern part of the country beset by militia violence.

More than 500 people, including health workers, have been vaccinated against the disease in Congo's latest outbreak, marked by 78 confirmed and probable cases, including 44 deaths, the WHO says.

About 1500 people have been identified as contacts of people infected with the disease that causes fever, vomiting and diarrhoea.

"We don't know if we are having all transmission chains identified. We expect to see more cases as a result of earlier infections and these infections developing into illness," WHO spokesman Tarik Jasarevic told a Geneva news briefing on Friday.

The outbreak has spread from its epicentre in North Kivu province to neighbouring Ituri province after an infected person returned home, Congo's health ministry said this week, complicating containment in a region beset by widespread militia violence.