Dawn has barely broken when Jonas Tahou enters the forest, trousers stuffed into knee-high rubber boots that sink in the mud as he marches silently through the trees and tangled vines.
Somewhere in this sweltering jungle, in the deep green thicket that blocks the sun and swallows up Tahou’s slender form, lives a killer rarely seen but always present, one that prowled the forest perhaps thousands of years before emerging 20 years ago to earn the name Ebola.
Two decades after the first known outbreak of the virus and 18 months after its deadly resurgence in the Zairian city of Kikwit, a fledgling international effort is under way in this remote rain forest along the Liberian border to track Ebola’s source before it strikes again.
Previous searches, including expeditions in Central Africa, have been unable to pinpoint the source.
As he moves deeper into the trees, the quiet broken only by the squish of his boots and the cries of the forest, Tahou checks dozens of traps placed on the ground to capture rodents. If he’s lucky, there will be a shrew or perhaps some mice or rats to take back to camp, euthanize and slice open to test their tissues for Ebola.
There are no high-tech labs with filtered air pumped in, no link-up with the Pentagon to report new discoveries, no helicopters to rush deadly samples to Europe or the United States. The traps Tahou checks are plastic buckets shoved into the mud; the tiny mammals are gassed in old sour cream cups; lab liquids are stored in wine bottles. There’s a jeep that works sometimes, a telephone two hours’ drive away, and a steamy autopsy room lit by one bare bulb when the generator is cranked up.
“Outbreak” it isn’t. But to the disparate group of men and women drawn together here - agile forest-dwellers like Tahou, a U.S. Army major and ex-rodeo rider, an Australian veterinarian who nurses her infant daughter between bat autopsies - it’s the best chance yet to crack the riddle of one of the deadliest viruses known.
The fear of new or re-emerging diseases has been underscored by the worldwide AIDS epidemic and by resurgent infections of tuberculosis, yellow fever and malaria that are increasingly resistant to drugs. Deaths from infectious diseases increased 56 percent from 1980 to 1992, according to the U.S. Centers for Disease Control and Prevention.
Perhaps no disease conjures up such terrifying images as Ebola, named after the Zairian river flowing through the region where it first appeared in 1976. Ebola kills up to 80 percent of its victims, causing them to bleed to death internally.
There’s no guarantee the Tai Forest project, with its shoestring $250,000 budget for two years, will succeed in finding the plant, animal or insect where the virus thrives when it’s not on its deadly rampage through humans. But there are signs the hunters are on the right track.
In June, two months after the project got under way, tissue from a Red Colobus monkey found dead in the forest tested positive for Ebola. The henna-colored apes are a major food source for chimpanzees, which in the past have also tested positive for Ebola.
That’s a clue Ebola might originate in the Red Colobus, though researchers say it probably isn’t that simple. With the monkeys living in large social groups with frequent physical contact, the virus likely would afflict more than just one at a time. One theory is the monkeys catch the virus from bats sharing the trees in which they live, or from one of the ground rodents that scamper up these trees and leave droppings on the leaves eaten by the Red Colobus.