Reviewed By Diana Stadelnikas, Vaccine Injury Attorney What is Encephalitis (Encephalopathy)? Encephalitis (en-sef-uh-LIE-tis), also known as encephalopathy, is a swelling of the brain.  Encephalopathy most is commonly triggered after a person contracts certain viruses or bacteria. If the virus or bacteria ends up traveling to the spinal cord or brain, it causes inflammation. This inflammation … Continue reading Encephalitis Triggered by a Vaccine Reaction