About the same time as the Hendra outbreak near Brisbane, another spillover occurred, this one in central Africa. Along the upper Ivindo River in northeastern Gabon, near the border with the Republic of the Congo, lies a small village called Mayibout II. In early February 1996, 18 people there became suddenly sick after they participated in the butchering and eating of a chimpanzee. Their symptoms included fever, headache, vomiting, bleeding in the eyes, bleeding from the gums, hiccuping, and bloody diarrhea. All 18 were evacuated downriver to a regional hospital, where four soon died. The bodies were returned to Mayibout II and buried, with no special precautions; a fifth victim escaped from the hospital, went back to the village, and died there. Secondary cases occurred among people infected by loved ones or friends, or in handling the dead bodies. Eventually 31 people got sick, of whom 21 died—a mortality rate of 68 percent.

Those facts and numbers were collected by a team of medical researchers, some Gabonese, some French, who reached Mayibout II during the outbreak. Among them was a Frenchman named Eric M. Leroy, based at the Centre International de Recherches Médicales de Franceville (CIRMF), in Franceville, Gabon. Leroy and his colleagues identified the disease as Ebola hemorrhagic fever and deduced that the butchered chimpanzee had been infected with Ebola virus. Their investigation also revealed that the chimp hadn't been killed by village hunters; it had been found dead in the forest and scavenged.

Four years later, I sat at a campfire near the upper Ivindo River with a group of local men working as forest crew for a long overland trek. (See "The Green Abyss: Megatransect, Part II," March 2001.) The men, mostly Bantu, had been walking for weeks before I joined them on the march. Their job involved carrying heavy bags through the jungle and building a new camp every night for the Wildlife Conservation Society biologist J. Michael Fay, whose extraordinary grit and sense of mission drove the enterprise forward. This particular day had been a relatively easy one—no swamps crossed, no charging elephants—which allowed for a relaxed, confiding atmosphere at the evening fire. I learned that two of the men, Thony M'Both and Sophiano Etouck, had been present in Mayibout II when Ebola struck the village. M'Both, slim in build, older, and more voluble than the others, was willing to talk about it. He spoke in French while Etouck, a shy man with wide shoulders, an earnest scowl, and a goatee, sat silent. Etouck's own family had been devastated by the disease. He had held one of his dying nieces in his arms, while an IV drip in her wrist became clogged, swelled her hand, and exploded, covering him with her blood. Yet Etouck himself never got sick. Nor did I, said M'Both. The cause of the illnesses was a matter of confusion and fearful rumor. M'Both suspected that French soldiers, visiting nearby, had killed the chimpanzee with some sort of chemical weapon and carelessly left it to poison unsuspecting people. But whatever the cause, whatever the contaminant, his fellow villagers had learned their lesson. To this day, he said, no one in Mayibout II eats chimpanzee.