The epicenter of the outbreak, which killed its first victim last month, is in the busy town of Isiro in Orientale Province, but it has spread to the settlement of Viadana 75 km (45 miles) away, the World Health Organisation (WHO) said in a statement.

WHO also called for aid of nearly $2 million to help Congo's weakened health sector cope with the disease.

Last month officials confirmed that the epidemic was a different strain from the one that killed at least 36 people in neighboring Uganda, and had likely been sparked by locals eating infected meat in the forest.

As of Sunday, there had been 29 confirmed or probable cases with 14 deaths and a mortality rate of around 48 percent, Anja de Weggheleire, medical co-ordinator in the area for the charity Doctors Without Borders (MSF), said.

"A week ago we were a bit optimistic ... but a few days later we got some more cases ... We have quite a clear picture of what is happening, but I cannot say it is under control," she said.

Officials say that nearly 170 people remain under surveillance to see if they develop symptoms of the disease and with the last confirmed case on Saturday, the end of the epidemic remains a long way off, de Weggheleire said.

Ebola is transmitted to humans from monkeys and birds and causes massive bleeding in victims. Mortality rates can be as high as 90 percent.

(Reporting by Jonny Hogg; Editing by David Lewis and Alison Williams)

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