"Fifty people have died since mid-October," the head of the Red Cross in Sierra Leone, John Marah, told AFP.
He said the toll is likely to rise.
"Nine people are now in the isolation centre and two of these are seriously ill, with not much hope for them I'm afraid," he said. "The situation is really difficult."
Some 60 cases of Ebola have been confirmed in the region and at least 200 people have been placed in quarantine, said Marah yesterday.
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It is thought the virus was brought to the area by a trader who died in the neighbouring province of Kono, some 30 kilometres away, before he was brought home.
The virus quickly spread among a disbelieving public.
"There was a lot of denial about Ebola at the beginning," said Marah, in an attempt to explain the initial slow response of the humanitarian agencies.
Foday Jalloh, chief of the Nieni region, told the Red Cross last Wednesday that several bodies were left for up to a week on village streets as people were afraid to touch the bodies, once fears about the virus spread.
"We need medical supplies and medical equipment, we need intervention to give us support," said Falloh.
Last week, the World Health Organization said that 13,268 people had been infected with Ebola across eight countries, and 4,960 of them had died.
The deadliest Ebola outbreak ever has hit Liberia, Guinea and Sierra Leone the hardest.
In its latest toll, the WHO said 2,766 deaths were recorded in Liberia, out of a total of 6,619 cases.
In Sierra Leone, 1,130 people had died from the virus out of 4,862 cases. In Guinea, there were 1,054 deaths from 1,760 cases.