
Encephalitis literally means an inflammation of the brain, but it usually refers to brain inflammation caused by a virus. It's a rare disease that occurs in approximately 0.5 per 100,000 individuals — most commonly in children, the elderly, and people with weakened immune systems (i.e., those with HIV/AIDS or cancer). Although several thousand cases of encephalitis (also called acute viral encephalitis or aseptic encephalitis) are reported to t