“Many illnesses (such as measles, mumps, …) are typically quite mild, easy to recover from and unlikely to cause long-term complications when contracted naturally during childhood.”

Mild? - Sure.
There are about 400 children dying from measles EVERY DAY.
10-20% of all sickened children get complications.

Really an awesome disease to have. It sickens me how you can really say that measles are typically quite mild.