By David Meduna, MD, FAAP
Fever is a common and distressing problem among children. We frequently receive calls about fever, and there is a lot of confusion about when to be concerned and when not to be concerned when your child has a fever.
Normal body temperature can range from 97 to 100.3 degrees Fahrenheit. Doctors consider a body temperature over 100.3 degrees Fahrenheit to be a fever. Some school systems consider temperatures over 99.9 degrees Fahrenheit as a fever. Fever is a normal body reaction to many infections. It slows the reproduction of many types of bacteria and viruses, helping us recover from these infections. Fevers over 103-104 degrees Fahrenheit don’t have any more benefit than fevers below this level. Therefore, treatment of fevers in healthy children can often be reserved until the fever exceeds 102 degrees Fahrenheit. Treatment is particularly important in children with heart, lung, or other chronic conditions, as fever may exacerbate these conditions. Always discuss with your health care provider how to manage fever in such cases.
A long-standing myth is that a high fever will damage the brain. Fevers must reach around 106 degrees Fahrenheit to cause brain damage, which is rare due to infections. However, fevers can get dangerously high if a child has too many clothes or blankets, as this can prevent heat from leaving the body. This is why we recommend removing extra clothing or blankets during high fevers. A sponge bath with lukewarm water may also help. Fevers caused by heat stroke or reactions to certain medications can get high enough to damage vital organs, requiring medical care as an emergency.
The critical question with fever is determining its cause. Fever can result from a mild, temporary viral infection to a more severe, life-threatening infection. Consider these guidelines:
When to notify your healthcare provider of a fever depends on your child’s age, as the type and severity of infections that children can get varies by age. If your child is:
- Birth-3 months: Call right away with any fever over 100.3 degrees Fahrenheit.
- Older than 3 months: Call right away with any fever over 105 degrees Fahrenheit.
In addition, always call your healthcare provider if any of the below apply:
- You are very concerned about your child.
- Fever is associated with shortness of breath, severely decreased activity, severe cough, or stiff neck.
- Your child has a fever with a very sore throat and/or known exposure to strep throat.
- Your child’s symptoms seem different from ordinary cold symptoms.
Fevers due to viruses often start early in an illness and usually subside after three days. While viral fevers may rarely last up to a week, you should consult a doctor if the fever persists for more than three days or returns after initially subsiding. Your healthcare provider will determine if follow-up is needed to rule out a more serious bacterial infection.
Here are some final thoughts about fever:
- Athletes should not train when they have a fever.
- A child with a viral illness is more likely to spread the virus when fever is present, and that is why we ask children with fevers to stay home from school until the fever is gone.
- Fevers will often break in the morning and return at night.