DEAR MAYO CLINIC: Ever since I had my son, I tend to worry whenever he gets ill, so I try to educate myself on different viruses and autoimmune disorders. I recently came across encephalitis. What is ...

Encephalitis is a disease referring to the inflammation or swelling of the brain. Broadly, it can happen because of infections, including viral infections, or the immune system acting up. That’s why ...

Have you ever found yourself searching for a word you should know, forgetting what you were just doing, or feeling mentally foggy for no obvious reason? These everyday lapses are common and are most ...