The word germs refers to bacteria , viruses, fungi and protozoa. The first type of germ is the most fascinating because we have lots of different types of bacteria in our body- 50 times more bacterial types than cells in our body! The scientists tell us that as the baby passes through the birth canal, they swallow “muck ” from Mum (!!!) and because they’ve very little acid in their stomach, the bacteria pass on into the various places in the body and live there. As to how they all originated, the belief is that “stray” DNA or RNA evolved to form these little critters!