The National Academies

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

What You Need To Know About Infectious Disease

New infectious diseases are emerging and old ones are appearing in new places around the globe. What’s behind this trend? And to what extent has human behavior amplified the problem? The National Academies, advisers to the nation in science, engineering, and medicine, provide the information you need to understand this complex topic.


Microbes are all around us. Most don’t do any harm, and many are beneficial, but what about the few that cause infection? Learn the basics.


Certain aspects of disease are a particular threat to us today. What are some of the things we're most concerned about in the United States?


National borders do little to block the path of infectious disease. Learn how our modern way of life contributes to the emergence and spread of diseases.


What do we need to do—as individuals and as a society—to stave off the threat of emerging infectious disease?

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What do you know about infectious disease?

Which are larger?

  • Correct!

    Bacteria are 10 to 100 times larger than viruses.

  • Sorry, that’s incorrect.

    Bacteria are 10 to 100 times larger than viruses.

Infectious Disease Defined


A poisonous substance, often a protein, produced by the metabolic processes of living cells or organisms that can cause disease if introduced into the body.

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Disease Watchlist


Meningitis is the inflammation of the meninges, the coverings of the brain and spinal cord. Meningitis is usually caused by either a virus or bacteria, and treatment differs depending on the cause. 

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