"As public health officials struggle to contain the Zika virus, science writer Sonia Shah tells Fresh Air's Dave Davies that epidemiologists are bracing themselves for what has been called the next "Big One" — a disease that could kill tens of millions of people in the coming years."

"Citing a 2006 survey, Shah says, 'the majority of ... pandemic experts of all kinds, felt that a pandemic that would sicken a billion people, kill 165 million people and cost the global economy about $3 trillion would occur sometime in the next two generations.'"

"In her new book, Pandemic: Tracking Contagions from Cholera to Ebola and Beyond, Shah discusses the history and science of contagious diseases. She notes that humans put themselves at risk by encroaching on wildlife habitats. 'About 60 percent of our new pathogens come from the bodies of animals,' she says."