Post-encephalitic parkinsonism is a disease believed to be caused by a viral illness that triggers degeneration of the nerve cells in the substantia nigra.

The onset of post-encephalitic parkinsonism may occur several years after the resolution of encephalitis lethargica.

[1] The brain regions affected contain neurofibrillary tangles, similar to those seen in Alzheimer's disease.

In post-encephalitic parkinsonism patients, however, the senile plaques common in Alzheimer's disease are not found.

Creutzfeldt–Jakob disease This article about a medical condition affecting the nervous system is a stub.