The National Academies: What You Need To Know About Infectious Disease

The National Academies

What You Need To Know About Infectious Disease

How Infection Works

Microbes occupy all of our body surfaces, including the skin, gut, and mucous membranes. Most don’t do us any harm—in fact, many help us survive. But there are certain bacteria, viruses, and other microbial life forms that can cause illness, or even death. Here we learn the basics about microbes and the fascinating relationship we have with them.

Microbes & Humans

A human body contains at least 10 times more bacterial cells than human ones.

Microbes and humans have evolved a complex relationship over thousands of years. Find out just how interconnected we are.

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Types of Microbes

There are five major categories of infectious agents. 

Viruses, bacteria, and helminths—oh my! Learn about the different microorganisms that are the source of infectious disease in people.

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Encountering Microbes

Microbes may be the earliest life forms on Earth.

People and microbes have always shared this planet. But changes in the way we live are affecting how and where we encounter microbes. Discover the impact of our modern way of life.

More about encountering microbes

How Pathogens Make Us Sick

Infection does not necessarily lead to disease.

Pathogens (microbes capable of causing disease) call our immune systems into action. Find out more about how the body responds to these tiny invaders.

More about how pathogens make us sick

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Infectious Disease Videos

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What You Need to Know About Infectious Disease

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What do you know about infectious disease?

How many people in the United States die from flu-related complications each year?

  • Sorry, that’s incorrect.

    About 36,000 people die from flu-related complications each year in the United States. More than 200,000 are hospitalized.

  • Correct!

    About 36,000 people die from flu-related complications each year in the United States. More than 200,000 are hospitalized.

  • Sorry, that’s incorrect.

    About 36,000 people die from flu-related complications each year in the United States. More than 200,000 are hospitalized.

Infectious Disease Defined

Protein
A type of complex organic compound made up of amino acids linked together by peptide bonds that performs a variety of essential functions in living organisms.

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National Academies Press

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