If a shared podium with Fauci proved that Daszak had become a true player among virus hunters, it also underscored just how far he had come. For years, Peter Daszak sat at the helm of a struggling nonprofit with a mission to save manatees, promote responsible pet ownership, and celebrate threatened species. The organization, which operated under the name Wildlife Trust until 2010, was constantly on the hunt for ways to close its budget shortfalls. One year, it proposed to honor at its annual benefit a mining company operating in Liberia that was paying it to assess the risks of Ebola virus. Another idea was to seek donations from palm-oil millionaires leveling rainforests who might be interested in “cleaning up” their image.

Balding and usually clad in hiking gear, Daszak was one part salesman, one part visionary. He saw clearly that human incursions into the natural world could lead to the emergence of animal pathogens, with bats a particularly potent reservoir. Daszak was “making a bet that bats were harboring deadly viruses,” said Dr. Matthew McCarthy, an associate professor of medicine at Weill Cornell Medical Center in New York. In 2004, as a 23-year-old Harvard medical student, McCarthy followed Daszak to Cameroon to trap bats. “I left my family, my friends,” he said. “It was a very powerful thing for people like me, going into the most remote parts of the world. I was taken by him, hook, line, and sinker.”

The bioterror attacks of 2001, in which letters dusted with anthrax spores were sent through the U.S. mail, coupled with the first SARS coronavirus outbreak in China the following year, would bring money for the study of let