Episode One: Spillover in Suburbia

A horse mysteriously falls ill in her paddock, and before long dozens of other horses from her stables are sick. As the horses start to die vicious, painful deaths, their trainer falls into a coma and is placed into intensive care. The race is on to figure out what's making both species sick, and where it came from. What they find will resonate throughout the following decades and might help us uncover the origins of COVID-19.

Presented by Olivia Willis

Patient Zero is a production of ABC Science, Radio National, and the BBC World Service.

Picture: Wild horses, Credit: Phil Copp/Getty Images