encephalitis lethargica

Encephalitis Lethargica: The Mysterious 'Sleeping Sickness' Epidemic

Encephalitis lethargica, a mysterious neurological illness dubbed the 'sleeping sickness,' emerged during the 1918 flu pandemic, causing extreme sleepiness and immobility. Survivors often developed Parkinson's-like symptoms, and its cause remains unknown over a century later, baffling scientists.