My children EMPTY the dishwasher. This is so not going to happen in my house!
I also think it depends on the dishwasher and the setting that you use it on. "Energy efficient" for example, and "no heat" dry probably don't sterilize.
But look at it from a different perspective. We live in a unclean world, and we make it cleaner than it used to be. The dishwasher (and more efficient) than handwashing used to be, and in general we survive. The body is designed to handle a certain amount of "non-clean" and actually builds resilience by doing so.
If you're terrified, then only buy the safest materials and boil them. (Life is too short to fret over every detail. It's a matter of looking at all angles and compromises.)