The National Academies

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

What You Need To Know About Infectious Disease

Influenza

Influenza, or flu, is a viral respiratory disease that can affect anyone, from babies to senior citizens. It is a seasonal disease, most prevalent in the fall and winter months. Flu is usually spread from person to person through coughing or sneezing, touching contaminated surfaces such as doorknobs and countertops, or direct hand contact.

Unlike the common cold, another viral respiratory illness, flu can be serious, causing life-threatening complications. During a typical flu season, an average of 5 to 20 percent of the population contract the disease, with more than 200,000 hospitalized.

Symptoms
In older people and those with a compromised immune system, flu can be a serious illness. Its symptoms include high fever, headache, extreme tiredness, dry cough, sore throat, runny or stuffy nose, muscle aches, and stomach symptoms, such as nausea, vomiting, and diarrhea. In most instances, a person is contagious from about 1 day before to 5 days after the onset of symptoms.

Treatment
For most people, rest, plenty of fluids, and fever-reducing medications are all that is necessary. The illness can last from 2 days to 1 week. People should stay home from work or school through the acute phase of the illness until 24 hours after the fever goes away. For people with severe symptoms, such as shortness of breath, chest pain, and dizziness, antiviral medications such as Tamiflu® may be needed. Usually, this medication is taken for 5 days.

Prevention
By far, the best way to prevent contracting the flu is to get a flu vaccine each year. The flu vaccine is made of dead viruses from prevalent strains, which vary from year to year. For this reason, it is important to receive the appropriate vaccine every year. Hygiene practices—such as avoiding unnecessary touching of the eyes, mouth, and nose; covering your mouth and nose when sneezing or coughing; and washing your hands frequently—will also help keep you healthy during the flu season.

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What do you know about infectious disease?

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. 

Infectious Disease Defined

Fungi

A taxonomic kingdom of spore-forming organisms distinct from plants, animals, and bacteria that includes microorganisms such as yeast and molds, as well as mushrooms.

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