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

What You Need To Know About Infectious Disease

An electron micrograph of an influenza virus, showing details of its structure.

Credit: Cynthia Goldsmith/CDC

Viruses

Viruses are tiny, ranging in size from about 20 to 400 nanometers in diameter. Billions can fit on the head of a pin. Some are rod shaped; others are round and 20 sided; and yet others have fanciful forms, with multisided “heads” and cylindrical “tails.”
Viruses are responsible for a wide range of diseases, including the common cold, measles, chicken pox, genital herpes, and influenza.
Viruses are simply packets of nucleic acid, either DNA or RNA, surrounded by a protein shell and sometimes fatty materials called lipids. Outside a living cell, a virus is a dormant particle, lacking the raw materials for reproduction. Only when it enters a host cell does it go into action, hijacking the cell’s metabolic machinery to produce copies of itself that may burst out of infected cells or simply bud off a cell membrane. This lack of self-sufficiency means that viruses cannot be grown in artificial media for scientific research or vaccine development; they can be grown only in living cells, fertilized eggstissue cultures, or bacteria.
 
Viruses are responsible for a wide range of diseases, including the common cold, measleschicken pox, genital herpes, and influenza. They also cause many of the emerging infectious diseases, among them AIDS, Ebola, and Zika.
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What do you know about infectious disease?

If you have strep throat, which of the following forms of medication can be used to effectively treat the infection?

  • Sorry, that’s incorrect.

    Because strep throat is caused by a bacterium called Streptococcus pyogenes, it is treatable with antibiotics but not antivirals. Currently there is no vaccine available to prevent strep throat.

  • Correct!

    Because strep throat is caused by a bacterium called Streptococcus pyogenes, it is treatable with antibiotics but not antivirals. Currently there is no vaccine available to prevent strep throat.

  • Sorry, that’s incorrect.

    Because strep throat is caused by a bacterium called Streptococcus pyogenes, it is treatable with antibiotics but not antivirals. Currently there is no vaccine available to prevent strep throat.

  • Sorry, that’s incorrect.

    Because strep throat is caused by a bacterium called Streptococcus pyogenes, it is treatable with antibiotics but not antivirals. Currently there is no vaccine available to prevent strep throat.

Infectious Disease Defined

National Institute of Allergy and Infectious Diseases (NIAID)

Part of the U.S. Department of Health and Human Services and the National Institutes of Health, NIAID conducts and supports basic and applied research to better understand, treat, and ultimately prevent infectious, immunologic, and allergic diseases.

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National Academies Press

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