If you don't want to get sick, don't be afraid of germs. Certainly you should wash your hands regularly, but medical professionals say use regular liquid soap, NOT antibacterial soap, as that gets rid of all germs, both good and bad. Whereas regular liquid soap only gets rid of the bad ones, while the good ones help you fight off illnesses. Also, hand sanitizer isn't very good for you either, and is also too sterilizing, not allowing you to get germs that will build your immune system.
Being surrounded by a moderate amount of germs will build your immune system, and so long as you are healthy otherwise you should be fine. It's really important that you get enough sleep, eat right, and are active. If any of those three things aren't where they should be, it doesn't matter what you do, you're not going to have a good foundation to stay healthy.