Clinical Reference Systems: Pediatric Advisor 10.0

Misconceptions about the dangers of fever are commonplace. Unwarranted fears about harmful side effects from fever cause lost sleep and unnecessary stress for many parents. Let the following facts help you put fever into perspective:

MYTH: All fevers are bad for children.

FACT: Fevers turn on the body's immune system. Fevers are one of the body's protective mechanisms.

Most fevers are good for children and help the body fight infection. Use the following definitions to help put your child's level of fever into perspective:

 

       100ƒF to 102ƒF     Low-grade fever: Beneficial. Try 
       (37.8ƒC to 39ƒC)   to keep the fever in this range.  

       102ƒF to 104ƒF     Moderate-grade fever: Beneficial. 
       (39ƒC to 40ƒC) 

       Over 104ƒF         High fever: Causes discomfort, but 
       (40ƒC)             is harmless. 

       Over 105ƒF         High fever: Higher risk of 
       (40.6ƒC)           bacterial infections. 

       Over 108ƒF         Serious fever:  The fever itself can 
       (42ƒC)             be harmful. 

MYTH: Fevers cause brain damage or fevers over 104ƒF (40ƒC) are dangerous.

FACT: Fevers with infections don't cause brain damage. Only body temperatures over 108ƒF (42ƒC) can cause brain damage. The body temperature goes this high only with high environmental temperatures (for example, if a child is confined in a closed car in hot weather).

MYTH: Anyone can have a febrile seizure.

FACT: Only 4% of children have a febrile seizures.

MYTH: Febrile seizures are harmful.

FACT: Febrile seizures are scary to watch, but they usually stop within 5 minutes. They cause no permanent harm. Children who have had febrile seizures do not have a greater risk for developmental delays, learning disabilities, or seizures without fever.

MYTH: All fevers need to be treated with fever medicine.

FACT: Fevers need to be treated only if they cause discomfort. Usually that means fevers over 102ƒF or 103ƒF (39ƒC or 39.4ƒC).

MYTH: Without treatment, fevers will keep going higher.

FACT: Wrong. Because of the brain's thermostat, fevers from infection top out at 105ƒF or 106ƒF (40.6ƒC or 41.1ƒC) or lower.

MYTH: With treatment, fevers should come down to normal.

FACT: With treatment, fevers usually come down 2ƒ or 3ƒF (1.1ƒ or 1.7ƒC).

MYTH: If the fever doesn't come down (if you can't "break the fever"), the cause is serious.

FACT: Fevers that don't respond to fever medicine can be caused by viruses or bacteria. Whether the medicine works or not doesn't relate to the seriousness of the infection.

MYTH: If the fever is high, the cause is serious.

FACT: If the fever is high, the cause may or may not be serious. If your child looks very sick, the cause is more likely to be serious.

MYTH: The exact number of the temperature is very important.

FACT: How your child looks is what's important, not the exact temperature.

MYTH: Temperatures between 98.7ƒF and 100ƒF (37.1ƒC to 37.8ƒC) are low-grade fevers.

FACT: The normal temperature changes throughout the day. It peaks in the late afternoon and evening. A low- grade fever is 100ƒF to 102ƒF (37.8ƒC to 39ƒC).

Reading Temperatures

• A reading of 99.4ƒF (37.4ƒC) is the average rectal temperature. It normally can change from 98.4ƒF (36.9ƒC) in the morning to a high of 100.3ƒF (37.9ƒC) in the late afternoon.
• A reading of 98.6ƒF (37ƒC) is just the average oral temperature. It normally can change from a low of 97.6ƒF (36.4ƒC) in the morning to a high of 99.5ƒF (37.5ƒC) in the late afternoon.