encephalitis lethargica

Encephalitis lethargica or von Economo disease is an atypical form of encephalitis. Also known as "sleepy sickness" (distinct from tsetse fly-transmitted sleeping sickness), it was first described in 1917 by the neurologist Constantin von Economo and the pathologist Jean-René Cruchet. The disease attacks the brain, leaving some victims in a statue-like condition, speechless and motionless. Between 1915 and 1926, an epidemic of encephalitis lethargica spread around the world; no recurrence of the epidemic has since been reported, though isolated cases continue to occur.