Our bodies are pretty amazing. Day after day, they work hard - digesting food , pumping blood and oxygen, processing signals from our nerves and our brains , and much more. There is one group of organisms, though, that can make our bodies break down - tiny invaders called germs. Some kids may think that germs are just bugs or cooties or other gross stuff. Actually, germs are tiny organisms that can cause disease.
Germs are so small and sneaky that they creep into our systems without being noticed.
In fact, germs are so tiny that you need to use a microscope to see them. Germs are found all over the world, in all kinds of places. They invade plants and animals and sometimes make us sick. Germs invade us because they can't live on their own. In some cases that environment is a human body.