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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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Disease Watchlist

What do you know about infectious disease?

True or False: Washing your hands with soaps that have residue-producing antibacterial products, such as those containing the chemical triclosan, have been proven to confer health benefits.

  • Sorry, that’s incorrect.

    Washing with regular soap is considered the most important way to prevent disease transmission. Routine consumer use of residue-producing antibacterial products has no added benefit and may actually contribute to antibiotic resistance.

  • Correct!

    Washing with regular soap is considered the most important way to prevent disease transmission. Routine consumer use of residue-producing antibacterial products has no added benefit and may actually contribute to antibiotic resistance.

Infectious Disease Defined

Centers for Disease Control and Prevention (CDC)

A federal agency under the U.S. Department of Health and Human Services that works with partners across the United States to ensure public health—through health promotion; prevention of disease, injury, and disability; and preparedness for new health threats.

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National Academies Press

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