[Viral Infection].

Viral central nervous system(CNS)infections due to direct viral infection in the CNS include encephalitis/myelitis and meningitis. Acute encephalopathy is a CNS disorder that is mainly associated with viral respiratory infections. This article outlines herpes encephalitis, poliomyelitis, enterovirus A71 brainstem encephalitis/myelitis, and enterovirus D68 paralytic myelitis as acute encephalitis/myelitis, enteroviral meningitis and mumps meningitis as acute viral meningitis, and influenza encephalopathy and HHV-6 encephalopathy as acute encephalopathy.