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

Encountering Microbes

Microbes have inhabited the earth for billions of years and may be the earliest life forms on the planet. They live in every conceivable ecological niche—soil, water, air, plants, rocks, and animals. They even live in extreme environments, such as hot springs, deep ocean thermal vents, and Antarctic ice. Indeed microbes, by sheer mass, are the earth’s most abundant life form and are highly adaptable to external forces. How does our modern lifestyle bring us into greater contact with infectious agents—the “bad” microbes? And when we encounter them, how do they get into our bodies?

New Meeting Places

Almost 2 million passengers, each a potential carrier of infection, travel daily by aircraft to international destinations.

International trade, expanded development into forest areas, and worldwide travel are just a few of the reasons people are increasingly coming into contact with infectious agents. Learn more about these new encounters.

More about new meeting places

Entering the Human Host

The most common vector for human infection is the mosquito, which transmits malaria, West Nile virus, and yellow fever.

What do sneezes, ticks, and raw meat have in common? They are all vehicles for pathogens (aka disease-causing microbes) to infect humans. Learn more about how infectious microbes spread.

More about entering the human host

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Infectious Disease Videos

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What You Need to Know About Infectious Disease

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Disease Watchlist

What do you know about infectious disease?

Which of the following is not a viral disease:

  • Sorry, that’s incorrect.

    Trichinosis is not a viral disease. It is caused by a helminth (parasitic worm) found in undercooked meat, not by a virus. 

  • Sorry, that’s incorrect.

    Trichinosis is not a viral disease. It is caused by a helminth (parasitic worm) found in undercooked meat, not by a virus.   

  • Correct!

    Trichinosis is not a viral disease. It is caused by a helminth (parasitic worm) found in undercooked meat, not by a virus.  

Infectious Disease Defined

Sperm Cell

The male gamete, or sex cell, which carries the hereditary material of the male parent and unites with the female egg cell during sexual reproduction.

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National Academies Press

Search the National Academies Press website by selecting one of these related terms.