In late 1916, while treating a group of patients at his psychiatric clinic at the University of Vienna, Dr. Constantin von Economo began noticing the appearance of strange symptoms that he could not account for. At the same time, in France, Rene Cruchet began noticing similarly strange and unexpected symptoms in his patients. Though the two men had never met and knew nothing of one another’s patients, they would come to learn they were both witnessing the emergence of a new mysterious disease that would soon affect millions of people around the world.

The illnesses documented by von Economo and Cruchet would eventually come to be know as encephalitis lethargica, or sleeping sickness, a strange condition that caused profound lethargy, hypersomnia, and a wide range of other frightening symptoms. Between 1919 and the early 1930s, millions of people all around the world contracted the illness, with nearly half of all cases resulting in death, and many more suffering long-term effects; yet a cause of the illness has never been established and the terrifying epidemic appears to have faded from memory not long after the disease itself ostensibly disappeared.

Brook, Harry Ellington. 1921. "Care of the body." Los Angeles Times, March 6: 18.

Crosby, Molly Caldwell. 2011. Asleep: The Forgotten Epidemic that Remains One of Medicine's Greatest Mysteries. New York, NY: Penguin Publishing Group.

Hassler, Dr. William. 1919. "No sleeping sickness in S.F." San Francisco Examiner, March 10: 1.

Hoffman, Leslie A., and Joel A. Vilensky. 2017. "Encephalitis lethargica: 100 years after the epidemic." Brain: A Journal of Neurology 2246-2251.

Montreal Star. 1920. "Sleeping sickness puzzling doctors." Montreal Star, January 15: 3.

New York Times. 1936. "Awakens from sleep continuing 440 days." New York Times, June 14: 13.

R.R. Dourmashkin, MD. 1997. "What caused the 1918-30 epidemic of encephalitis lethargica?" Journal of the Royal Society of Medicine 515-520.

Sacks, Oliver. 1973. Awakenings. New York, NY: Vintage.

San Francisco Examiner. 1919. "New sleeping sickness hits S.F. residents." San Francisco Examiner, March 14: 1.

—. 1921. "Ten succumb to sleeping sickness." San Francisco Examiner, August 18: 13.

Western Morning News. 1919. "Notices." Western Morning News, January 1: 1.

Williams, David Bruce. 2020. "Encephalitis Lethargica: The Challenge of Structure and Function in Neuropsychiatry." Archives of Medicine and Health Sciences 255-262.

Wright, Oliver. 2002. "His life passed in a trance but his death may solve medical." The Times, December 14.

Cowritten by Alaina Urquhart, Ash Kelley & Dave White (Since 10/2022)

Produced & Edited by Mikie Sirois (Since 2023)

Research by Dave White (Since 10/2022), Alaina Urquhart & Ash Kelley

Listener Correspondence & Collaboration by Debra Lally

Listener Tale Video Edited by Aidan McElman (Since 6/2025)

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