Encephalitis literally means an inflammation of the brain, but it usually refers to brain inflammation caused by a virus. It may also be called “acute viral encephalitis or aseptic encephalitis”. Encephalitis is an infectious disease of the Central Nervous System characterized by pathologic changes in both the gray and white matter of the spinal cord and brain. It may be due to specific disease entity such as rabies or an arthropod-borne virus (arbovirus), or it may occur as a sequela of influenza, measles, German measles, chick ....