The National Academies

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

What You Need To Know About Infectious Disease

What do you know about infectious disease?

True or False: Infection with a pathogen (a disease-causing microbe) does not necessarily lead to disease.

  • Correct!

    Infection occurs when viruses, bacteria, or other microbes enter your body and begin to multiply. Disease follows when the cells in your body are damaged as a result of infection, and signs and symptoms of an illness appear.

  • Sorry, that’s incorrect.

    Infection occurs when viruses, bacteria, or other microbes enter your body and begin to multiply. Disease follows when the cells in your body are damaged as a result of infection, and signs and symptoms of an illness appear.

Since the beginning of the 20th century, the number of people in the world has: 

  • Sorry, that’s incorrect.

    Since the beginning of the 20th century the number of people in the world has more than quadrupled—from 1.6 billion to nearly 7 billion—and world population is expected to rise to well over 9 billion by 2050.

  • Sorry, that’s incorrect.

    Since the beginning of the 20th century the number of people in the world has more than quadrupled—from 1.6 billion to nearly 7 billion—and world population is expected to rise to well over 9 billion by 2050.

  • Correct!

    Since the beginning of the 20th century the number of people in the world has more than quadrupled—from 1.6 billion to nearly 7 billion—and world population is expected to rise to well over 9 billion by 2050.

Roughly how many microbes live in the human gastrointestinal tract?

  • Sorry, that’s incorrect.

    About ten trillion microbes live in the human gastrointestinal tract. They are essential for proper digestion and absorption of nutrients.

  • Sorry, that’s incorrect.

    About ten trillion microbes live in the human gastrointestinal tract. They are essential for proper digestion and absorption of nutrients.

  • Sorry, that’s incorrect.

    About ten trillion microbes live in the human gastrointestinal tract. They are essential for proper digestion and absorption of nutrients.

  • Correct!

    About ten trillion microbes live in the human gastrointestinal tract. They are essential for proper digestion and absorption of nutrients.

About how many airline passengers cross international borders daily?

  • Sorry, that’s incorrect.

    An estimated 1.8 million airline passengers cross international borders daily, creating routes by which human infections can radiate around the world within hours.

  • Sorry, that’s incorrect.

    An estimated 1.8 million airline passengers cross international borders daily, creating routes by which human infections can radiate around the world within hours.

  • Correct!

    An estimated 1.8 million airline passengers cross international borders daily, creating routes by which human infections can radiate around the world within hours.

True or False: Not all microbes are harmful to humans.

  • Correct!

    Not all microbes are harmful to humans. In fact, many of them protect us, helping our bodies function properly and competing with harmful organisms in an eternal contest for habitable space in or on our bodies. Although the microorganisms that cause disease often receive more attention, most microorganisms do not cause illness.

  • Sorry, that’s incorrect.

    Not all microbes are harmful to humans. In fact, many of them protect us, helping our bodies function properly and competing with harmful organisms in an eternal contest for habitable space in or on our bodies. Although the microorganisms that cause disease often receive more attention, most microorganisms do not cause illness.

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.

True or False: Our bodies contain at least 10 times more human cells than bacterial cells.

  • Sorry, that’s incorrect.

    Our bodies contain at least 10 times more bacterial cells than human cells. 

  • Correct!

    Our bodies contain at least 10 times more bacterial cells than human cells. 

True or False: Scientists believe that hot weather may speed up both the breeding cycle of mosquitoes and replication of the virus in insects’ guts.

  • Correct!

    Scientists believe that hot weather may speed up both the breeding cycle of mosquitoes and replication of the virus in insects’ guts.

  • Sorry, that’s incorrect.

    Scientists believe that hot weather may speed up both the breeding cycle of mosquitoes and replication of the virus in insects’ guts.

Which of the following is NOT a type of infectious agent?

  • Sorry, that’s incorrect.

    White blood cells are not a type of infectious agent. Part of the immune system, white blood cells fight infection rather than cause it. 

  • Sorry, that’s incorrect.

    White blood cells are not a type of infectious agent. Part of the immune system, white blood cells fight infection rather than cause it. 

  • Correct!

    White blood cells are not a type of infectious agent. Part of the immune system, white blood cells fight infection rather than cause it. 

  • Sorry, that’s incorrect.

    White blood cells are not a type of infectious agent. Part of the immune system, white blood cells fight infection rather than cause it. 

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Explore Other Topics

Disease Watchlist

Infectious Disease Defined

Pandemic

An increase in the occurrence of a particular disease over a very large region, such as a continent or the entire globe, that is greater than what is expected over a given period of time.

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