I am a measles survivor as are my parents, all of my siblings, nearly my entire 5th grade class, most of the school.
I know in rare cases it can be a dangerous, but I don't think many have looked into how rare those problems are. As the population gets "younger" nobody remembers many of us have had - Measles, Mumps, Chickenpox, Whooping Cough. You would think I would be a mess having had all of those dangerous illnesses.