Nervous system affections caused by the mumps virus.

Hippocrates probably first described mumps parotitis, but not until 1758 was affection of the central nervous system reported in this disease. Mumps meningitis, encephalitis, myelitis, polyradiculitis and cranial neuritis are now well known, and may occur without clinical parotitis. Meningitis occurs most commonly, encephalitis, cranial neuritis and polyradiculitis less often, and myelitis rarely. They may present individually or in combination. A patient is described who first developed acute mumps meningoencephalitis, without clinical parotitis. Transverse myelitis occurred two weeks later, and finally optic neuritis ten days following the myelitis. Slow but complete recovery followed. Attention is directed to the various ways mumps can affect the nervous system. This virus should always be considered among possible etiologic agents causing such neurologic syndromes.