Conditions + Treatments

Fever Symptoms & Causes

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In-Depth

What causes a fever?

When your child has a fever, her body works the same way to control the temperature but it resets its thermostat at a higher temperature. The temperature increases for a number of reasons:

  • Chemicals called cytokines or mediators are produced in the body in response to an invasion from a microorganism, malignancy or other intruder.
  • The body is making more macrophages, which are cells that go to combat when intruders are present in the body. These cells actually “eat up” the invading organism.
  • The body is busily trying to produce natural antibodies which fight infection. These antibodies will recognize the infection next time it tries to invade.
  • Many bacteria are enclosed in an overcoat-like membrane. When this membrane is disrupted or broken, the contents that escape can be toxic to the body and stimulate the brain to raise the temperature.

What conditions can cause a fever?

The following conditions can cause a fever:

What are the benefits of a fever?

A fever actually helps the body destroy its microbial invader. It also stimulates an inflammatory response, which sends all kinds of substances to the area of infection to protect the area, prevent the spread of the invader, and start the healing process.

What are the symptoms that my child may have a fever?

Children with fevers may become more uncomfortable as the temperature rises. The following are the most common symptoms of a fever. However, each child may experience symptoms differently. In addition to a body temperature greater than 100.4 degrees Fahrenheit, symptoms may include:

  • Your child may not be as active or talkative as usual.
  • She may seem fussier, less hungry or thirstier.
  • Your child may feel warm or hot. Remember that even if your child feels like she is “burning up” the actual rectal or oral temperature may not be that high.

The symptoms of a fever may resemble other medical conditions. According to the American Academy of Pediatrics, if your child is younger that two months of age and has a rectal temperature of 100.4 degrees Fahrenheit or higher, you should call your pediatrician. If you are unsure, always consult your child’s physician for a diagnosis.

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