Many people don't even realize that each of us human beings is actually an ecology of microbial life, living symbiotically with human cells. We are a biome of billions of tiny life forms essential to our physiological functions.
The reason I don't fear germs, bacteria, etc. is because not only are they throughout our body- they are everywhere!
Research is showing that microbes even live in the air, all the way up to the very edge of our atmosphere. I saw an article on Neatorama about living organisms that survive floating miles up, at the edge of space.
Here is the National Geographic article with more info about the research: