Starting in 1915, a strange disease began spreading around the world that would terrify millions of people.
The illness was called encephalitis lethargica, but most people knew it as sleeping sickness. At first, victims would get what seemed like a regular cold or flu. They would feel tired and sick, with a sore throat and headache. But then something much worse would happen. They would start falling into a deep sleep that they could not wake up from properly.
