Actually, the notion that a dog's mouth is cleaner than a human's is a myth.
Obviously we have germs all over us. And in our mouths. Obviously, there's nothing you can do about that. I'm just talking about when I'm riding in the subway. Someone might sneeze, get some something on their hands, then hang onto to pole. Then I touch the same spot on my way to a restaurant, and touch my straw, bread, or whatever else I put in my mouth. So saying we have germs in our mouth is irrelevant - there's nothing we can do about that and they don't make us sick.
"If you are going to do something, do it well. And leave something witchy."
-Charlie Manson