What is a fever?

A fever is a higher-than-normal body temperature. It is a part of the body's natural response to infection.

The average normal body temperature is 98.6° Fahrenheit (or 37° Celsius). When your body's temperature rises a few degrees above normal, it is a sign that your body is fighting infection and is generally not cause for concern.

In these cases, a fever is the response you want your body to have since it means that it is healthy enough to fight infection. For this reason it is not always a good idea to try and bring a fever down too quickly. However, a fever that goes above 102°F (38.9° C) should be treated.

What are symptoms of a fever?

Symptoms of a fever include:

  • Elevated temperature
  • Chills
  • Aches
  • Lack of energy
  • Flushed complexion

Last reviewed by a Cleveland Clinic medical professional on 01/23/2019.


  • Hague R. Managing the child with a fever. Practitioner. 2015;259(1784):17-21, 2-3.
  • Tess AV. Chapter 8. Fever. In: Henderson MC, Tierney LM, Jr., Smetana GW. eds. The Patient History: An Evidence-Based Approach to Differential Diagnosis. New York, NY: McGraw-Hill; 2012. library.ccf.org
  • NHS Choices. Fever in children. Accessed 2/27/2019.

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