When new diseases spread, news reports often focus on wildlife culprits--rodents, monkeys and mpox; bats and COVID-19; waterfowl and avian flu; or mosquitoes and Zika. But, in this urgent and engaging book, we see it often works the other way around--humans have caused diseases in other animals countless times, through travel and transport, the changes we impose on our environment, and global warming. With science journalist Liz Kalaugher as our guide, we meet the wildlife we have harmed and the experts now studying the crosscurrents between humans, other animals, and health.

Herds of buffalo in Kenya, cloned ferrets in Colorado, and frogs shipped worldwide as living pregnancy tests for humans, all help Kalaugher dive into the murky backstories behind wildlife epidemics past and present. We learn that military conflict likely contributed to the spread of rinderpest, or cattle plague, throughout Africa, devastating pastoral communities. That crowded poultry farms may create virulent new forms of bird flu that spill back into the wild. And that West Nile virus--which affects not only birds and humans, but other animals, including horses, skunks, and squirrels--is spreading as global temperatures rise.

Expanding today's discussions of environmental protection to include illness and its impact, Kalaugher both sounds the alarm and explores ways to stop the emergence and spread of wildlife diseases. These solutions start with a simple lesson: when we protect other animals, we protect ourselves.