Almost a hundred years ago, the world faced a strange epidemic that caused people to sleep uncontrollably due to a condition known as "sleeping sickness." Victims would fall into a deep slumber so profound that those affected often did not wake up for weeks or even months at a time. The disease was deadly as well, killing between 30 to 40% of those infected due to respiratory failure. This illness appeared in Northern France in 1916 and caused individuals to enter a deep and prolonged sleep. The disease swept across Europe, then to India, Central America, and North America, until it receded and was almost entirely gone by 1930. However, to this day, no one knows exactly how it spread, what caused it, or whether the disease could return.
The illness is officially named encephalitis lethargica, or sleeping sickness, and initially caused flu-like symptoms, including headaches, nausea, joint pain, and fever. From there, it spreads to the eyes, leading to lack of coordination followed by double vision. Eyelids begin to droop, and patients become overwhelmed by the need for sleep day and night. Although they can often be awakened, patients quickly return to sleep, with many experiencing nightmares. Some, however, would slip into a coma.
The emergence of sleeping sickness around the same time as the Spanish flu pandemic led some to believe it might be linked to the H1N1 virus that claimed up to 50 million lives worldwide. However, analyses then and more recently, thanks to well-preserved brain samples, showed no evidence of bacteria or viruses that could cause such a reaction. Others theorize it could be an autoimmune response, or an exaggerated reaction by the body due to a cold (rhinovirus) or influenza virus, rather than a result of the infection itself. While this is a plausible explanation, it does not account for how the disease appeared and disappeared so rapidly.
Sadly, while the disease itself stopped spreading, the lives of those affected did not return to normal. Many of them developed Parkinson’s disease, with symptoms ranging from tremors to a complete inability to move their muscles.
