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

The National Academies

What You Need To Know About Infectious Disease


Pneumonia is an inflammation of the lungs most often caused by bacteria or viruses present in the environment. In most instances, these organisms cause only a mild form of the disease. Pneumonia is more worrisome in adults older than age 65 and individuals with compromised immune systems. In addition, the strains of pneumonia acquired in health care settings can be virulent. The bacteria present in these strains tend to become resistant to standard antibiotics quickly, resulting in types of pneumonia more difficult to treat.

Typical symptoms of pneumonia include cough, shortness of breath, lower than normal body temperature (in older people), sweating, shaking and the chills, chest pain, headache, muscle pain, and fatigue. Because pneumonia is a serious illness, it is important to go to the doctor if the cough persists, especially if it is accompanied by shortness of breath and the chills. Older adults should contact their doctors immediately, as should those with other medical conditions.

Before pneumonia can be treated, it is important to diagnose the organism that is causing it. If it is a bacterial infection, identifying which bacteria is the culprit will allow doctors to prescribe the appropriate antibiotic. If the illness is caused by a virus, antiviral medication can be used. Aspirin, ibuprofen, or acetaminophen are helpful for reducing the fever, and cough medicine provides some relief from the cough that often accompanies pneumonia. For older adults who are having trouble breathing, admission to the hospital may be warranted.

Because pneumonia may result from a bout of seasonal flu, avoiding that illness by getting the seasonal flu vaccine is a clear preventive measure. Adults older than age 65 should be vaccinated for Streptococcus pneumoniae, the most common form of the disease. Eating properly, following basic sanitation guidelines such as washing your hands frequently, getting enough sleep, exercising, and not smoking also go a long way toward keeping people healthy.


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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

Latent Infection

A type of persistent viral infection in which the virus is not currently producing additional viral offspring, but could later be reactivated and begin producing copies of the virus without the host being re-infected.

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