Kikwit, Zaire -- The deadly Ebola epidemic appears to be slowing amid evidence that the virus itself is weakening as it passes from person to person.

Although scientists in Kikwit warn that the virus remains unpredictable, they are cautiously expressing hope that Ebola may be burning itself out.

"We're settling in for a long haul here, . . . but it does seem like the epidemic is winding down," Dr. David Heymann of the World Health Organization said yesterday.

Virologists searching for the origins of the outbreak are also feeling hopeful. They now are focusing on a rainforest outside Kikwit, where the man believed to be the outbreak's first case worked as a farmer and charcoal gatherer. The forest is rife with bats, rats and mice, which the scientists are now trapping in hopes of finding the elusive Ebola carrier.

New scientific teams will soon be arriving in Kikwit, to scour the Bandundu province in search of other cases and clues as to the origin of the hemorrhagic fever virus. They will replace those who have been focused mostly on stopping the deadly epidemic.

When Heymann and the rest of the international team arrived in Kikwit 2 1/2 weeks ago, Ebola was spreading at a terrifying pace, the number of cases quadrupling every three days. But even as the toll went over 100 this week, there has been a slowdown. Only two deaths and no more than a handful of new cases have been reported.

Prevention efforts, such as persuading Kikwit residents to stop washing the bodies of their dead and thus touching contaminated body fluids, have clearly played a role.

But researchers say it also seems that the virus is becoming less virulent as it passes through more people.

The charcoal gatherer, for instance, fell ill Jan. 6 and died of Ebola in Kikwit that month. Seven out of 12 family members also died of the disease, having touched his body. The people who cared for that second generation of Ebola cases in the family also became infected and died.

But by the time the virus had been passed through four generations of transmission, it simply stopped, the team said. This occurred in March, well before the world knew that there was Ebola in Kikwit.

The virus seemed, as scientists here put it, to have "burned itself out."

Time will tell whether a similar pattern will manifest itself throughout Zaire. But scientists are now guardedly optimistic, noting that at least three more recent trails of transmission also seem to have ground to a halt.

There is also some excitement among the virologists who are focusing on a rainforest area some 30 kilometers outside Kikwit where the charcoal gatherer worked. He burned forest wood to make charcoal, which he sold as fuel in Kikwit.

Close examination of the area, known as Foret Pont Mwembe, revealed that "the forest seems virtually lifeless," said Dr. Robert Swanepoel of the National Institute of Virology in Johannesburg, South Africa. Mammals such as monkeys and antelopes have been hunted to extinction. But Swanepoel has found the area full of bats, rats, mice and snakes. They are now trapping the animals and analyzing their blood and tissues in hopes of finding where the Ebola virus resides between human outbreaks.