Brain and Central Nervous System Infections: Viruses

Several viruses are neurotropic, resulting in a multitude of clinical presentations, including acute or chronic meningitis, encephalitis, myelitis, polyradiculitis, and peripheral neuropathy. All segments of the nervous system, central or peripheral, can be involved in viral infections. Viruses can directly affect the nervous system, such as in meningitis and encephalitis, or indirectly (parainfectious or postinfectious) from inflammatory or immunologic reactions, such as in Guillain-Barré syndrome (GBS) or acute disseminated encephalomyelitis (ADEM).