Why people risk their lives to milk deadly snakes

As many as 137,000 people die from venomous snake bites every year. High quality antivenoms exist, but they're expensive and hard to make. In Australia, Billy Collett risks his life by milking hundreds of venomous snakes a week. Antivenom also requires plasma from animals like horses. We traveled the globe to learn why snake bites are still a global health emergency, and why antivenom production still requires animals.