encephalitis lethargica

Last reviewed 04/2023

Encephalitis lethargica was an epidemic of an encephalitic illness which occurred between 1918 and 1930 that left in its wake a severe extrapyramidal syndrome of parkinsonism with added dystonic movement disorders. Several survivors of the illness were left permanently disabled.

It was characterised by increasing stiffness, apathy, bradykinesia, drowsiness, weakness and tremor. Oculogyric crises were a common feature of encephalitis lethargica.

Rarely, patients suffer obsessional symptoms.

There are occasional sporadic cases of the disease seen in the UK.

The disease, and the temporary relief from its symptoms is the subject of the book and film "Awakenings" by Dr. Oliver Sachs.