Germs: Understand and protect against bacteria, viruses and infection
Germs — Learn how germs work and what you can do to protect yourself.
By Mayo Clinic Staff
Germs live everywhere. You can find germs (microbes) in the air; on food, plants and animals; in soil and water — and on just about every other surface, including your body.
Most germs won’t harm you. Your immune system protects you against infectious agents. However, some germs are difficult enemies because they’re constantly mutating to breach your immune system’s defenses. Knowing how germs work can increase your chances of avoiding infection.
Infectious agents: From bacteria to worms
Infectious agents come in many shapes and sizes. Categories include:
Bacteria are one-celled organisms that can be seen only with a microscope. They’re so small that if you lined up a thousand of them end to end, they could fit