Washing your hands often may prevent spreading diseases. When should you wash your hands? According to the CDC (Center for Disease Control):
Before, during, and after preparing food
Before eating food
Before and after caring for someone who is sick
Before and after treating a cut or wound
After using the toilet
After changing diapers or cleaning up a child who has used the toilet
After blowing your nose, coughing, or sneezing
After touching an animal, animal feed, or animal waste
After handling pet food or pet treats
After touching garbage
So, you pretty much have to wash your hands like 10-20 times day.
I think the CDC left off some other times when you should wash your hands. I would add:
After shaking hands with someone. "Hi, nice to meet you. Excuse me, I have to go wash off the germs you just infected me with."
Before, during and after sex
Before and after using your TV remote control
Before and after typing on a computer keyboard
Before, during and after using your dirty, filthy cell phone
AFTER washing your hands, because the faucet was full of germs when you touched it
After touching money. Unless you have a lot of it.
After voting for any politician