Many antibiotic pills we’ve relied on for decades to treat infections no longer work. It’s a global crisis. Hospitals are increasingly stumped. But where do resistant bugs come from?

 In our final episode of this season’s Prognosis, Bloomberg Senior Editor Jason Gale takes us to Copenhagen, Denmark, where one scientist searches for clues in airplane waste from all over the globe. He found killer superbugs thriving in healthy people from countries far and wide. Even in countries where antibiotic use has been strictly controlled, resistant bacteria have made their way to people via the food chain. Yet it’s not too late to turn back