FREDERICK -- Dressed in thick rubber gloves, surgical garb and a helmet that fed him microbe-free air, Capt. Neal E. Woollen spent workday afternoons over the past two months standing in a clearing in an African forest, dissecting gazelles, lizards, monkeys, mongooses and jackals.
The Army veterinarian was part of an international team of scientists sent to the city of Kikwit, in central Zaire, after an outbreak of the lethal Ebola virus. That outbreak has infected 296 people and killed 233 -- a mortality rate of almost 80 percent. No new cases have been reported since June 20.
He arrived in Zaire on June 6 with a team of U.S. scientists, assembled by the U.S. Centers for Disease Control and Prevention, to help search for Ebola's reservoir, or natural host. That's the plant or animal where the microbe resides, with less lethal effect, between rare epidemics.
They also hunted for Ebola's vector, the way the virus moves from its host to its human prey. In bubonic plague, for example, fleas are the vectors that transmit the bacterium from its principal host, rats, to humans.
Mornings, Captain Woollen said, he bounced through the bush in four-wheel-drive Land Cruisers, checking traps and shopping for domestic and wild animals in village markets. Afternoons, he worked in his makeshift, open-air laboratory, wearing his heavy protective gear in the mud, 90-degree heat and sopping humidity. He packed his tissue samples for shipment back to the CDC in Atlanta.
In their search, investigators retraced the path of the first known victim of the most recent Ebola outbreak, a Kikwit man who trekked almost 10 miles from his home each day to a patch of forest. There, he felled trees, turned them into charcoal and brought the fuel back to the city to sell. He and 10 members of his family eventually died of the illness.
Normally, Captain Woollen works at the Army Medical Research Institute of Infectious Diseases at Fort Detrick, which conducts research on how to defend against microbes that have been used, or might be used, as weapons of war. He returned from Zaire on July 22.
The 39-year-old scientist, who grew up on a farm in the grasslands of western Nebraska and received his veterinary degree from Kansas State University, worked for the U.S. Department of Agriculture before coming to Fort Detrick. He lives in West Virginia.
His parents, brother, aunts and uncles, most of them back in Nebraska, all said they were concerned when they found out he was joining the Ebola hunt. "My family's pretty low-key about things like that," he said. "They told me, 'Just be safe.' "
But he said he had no qualms about volunteering to track down one of the world's deadliest microbes. "When you're trained in doing medical work in infectious disease, you're trained to be careful and cautious, you know what the potential risk factors are," he said.
Ebola, which dissolves organs, blood cells and connective tissue and causes massive internal bleeding, appears to be transmitted to humans most often by contact with infected blood or other bodily fluids. In Kikwit -- a sprawling, dusty city of 400,000 -- only a relatively small number of residents were infected, many of XTC them health care workers and relatives of the victims.
"It's very easy to get things out of perspective," Captain Woollen said. "There's a lot of people living in Kikwit, and a few people dying."
On several occasions he would arrive in a village shortly after a funeral of an Ebola victim. While he couldn't always understand what the villagers were saying, there was no mistaking how they felt.
There were tears, he said. There was mourning. There was anguish. And there was gratitude, as well, that medical sleuths were trying to track the virus to its lair.
"These people were very interested in seeing work done on the disease," he said.
Another Fort Detrick scientist, Russell Coleman of New Market, went to Zaire to collect insects that might serve as the virus' reservoir or vector. He returned in June.
Now most of the fieldwork is finished. Microbiologists at the CDC in Atlanta are busy examining thousands of biological samples and testing them for the presence of Ebola.
Virologists have tried unsuccessfully to trace Ebola's path from other organisms to humans since the first outbreaks occurred in Africa in 1976.
"This is a very crafty, a very wary, a very elusive virus," said Bob Howard, a CDC spokesman.