<unk>  is an atypical form of encephalitis. Also known as "sleeping sickness" or "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<unk>  spread around the world. The exact number of people infected is unknown, but it is estimated that more than one million people contracted the disease during the epidemic, which directly caused more than 500,000 deaths. Most of those who survived never returned to their pre-morbid vigour. In the words of the famed neurologist and writer Oliver Sacks: They would be conscious and aware – yet not fully awake; they would sit motionless and speechless all day in their chairs, totally lacking energy, impetus, initiative, motive, appetite, affect or desire; they registered what went on about them without active attention, and with profound indifference. They neither conveyed nor felt the feeling of life; they were as insubstantial as ghosts, and as passive as zombies.No recurrence of the epidemic has since been reported, though isolated cases continue to occur.
Encephalitis lethargica
Japanese encephalitis
Powassan encephalitis
Eastern equine encephalitis
Saint Louis encephalitis
Brain fever
Tick-borne encephalitis
Limbic encephalitis