A mumps virus enters the body, then enters a cell. There it makes copies of itself. How does the immune system respond? It's up to you to figure it out. A play-by-play explanation will follow ...

Measles is a virus that can lead to ear infection, pneumonia, seizures, brain damage, and death. Measles is spread from person to person through airborne droplets and is very contagious. Mumps is a ...