Relapsing and remitting viral diseases of the nervous system

Johnson, Richard T.

Abstract Virus infections can recur intermittently as is painfully appreciated by sufferers of recurrent lesions caused by the herpesvirus. The mechanisms of viral exacerbation and remission have become of interest in the neurosciences with circumstantial evidence that some role is played by viruses in multiple sclerosis. Epidemiological data indicate that multiple sclerosis results from exposure to a virus in childhood followed by a long latency period. The clinical course is typically remitting and relapsing, and the brain and spinal cord contain multifocal demyelinative lesions of different ages. Studies of slow viral infections have now provided many explanations for long incubation periods and studies of both acute and persistent viral infections have shown varied mechanisms of demyelination. Several recent studies of latent and persistent viral infections have provided thought-provoking data on episodic disease.