Understanding Microbes in Sickness and in Health

Microbes are tiny organisms too tiny to see without a microscope, yet they are abundant on Earth. They live everywhere in air, soil, rock, and water. Some live happily in searing heat, while others thrive in freezing cold. Some microbes need oxygen to live, but others do not.

These microscopic organisms are found in plants and animals as well as in the human body. Some microbes cause disease in humans, plants, and animals. Others are essential for a healthy life, and we could not exist without them. Indeed, the relationship between microbes and humans is delicate and complex.

In this booklet, we will learn that some microbes keep us healthy while others can make us sick. Most microbes belong to one of four major groups: bacteria, viruses, fungi, or protozoa. A common word for microbes that cause disease is “germs.” Some people refer to disease-causing microbes as “bugs.” “I’ve got the flu bug,” for example, is a phrase you may hear during the wintertime to describe an influenza virus infection.

Content:
What Are Microbes?
Microbes Have Bothered Us for Millennia
Microbes Can Make Us Sick
Microbes Can Infect Us
Some People Are Immune to Certain Diseases
Microbes Cause Different Kinds of Infections
You Can Prevent Catching or Passing on Germs
When You Should Go to the Doctor
Infectious Diseases Are Diagnosed in Many Ways
Infectious Diseases Are Treated in Many Ways
“New” and “Old” Microbes Emerge on the Scene
Research
Glossary

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