Akademik

an encephalitis that was epidemic between 1915 and 1926; symptoms include paralysis of the extrinsic eye muscle and extreme muscular weakness

See sleeping sickness (def. 2).

lethargic encephalitis,

a form of inflammation of the brain believed to be caused by a virus, characterized by extreme drowsiness or lethargy, sometimes followed by stupor or paralysis; sleeping sickness; encephalitis lethargica.