Fever is a symptom of illness, and it is the body’s way of fighting off infection. While parents often fear fever in their children, it is a healthy response to illness and typically not harmful or life-threatening, unless it is extremely high, as in over 107° F (measured rectally). Most fevers are caused by common infections that are not serious.
Normal body temperature averages 98.6° F, although it can fluctuate throughout the day, from 97.4° F in the morning to 99.6° F in the late afternoon. A child’s temperature can increase from exercising, taking a hot bath, being outdoors when it’s hot, or wearing heavy clothes.
In babies and young children under 4 or 5 years old, you will get the most accurate reading from a rectal thermometer. A rectal temperature greater than 100.4° F indicates a fever. If you take the temperature in the armpit, a reading above 99° F indicates fever. Most pediatricians recommend against using an ear or temporal artery thermometer, as these are often not accurate.
For older children, you can use an oral thermometer. An oral reading above 100° F indicates fever.
The most common causes of fever in children include viral infections, bacterial infections, and immunizations. Toddlers and young children are especially prone to fevers. In fact, many children this age experience 7 to 1 viral infection a year. A common thought among parents is that teething may cause fever, but it does not.
Signs and symptoms of fever may vary according to your child’s age. If your child is too young to speak or verbalize the way he feels physically, the following symptoms may indicate a fever:
- Irritable or fussy
- Quiet or lethargic
- Feel warm or hot
- Decreased appetite
- Changes in sleeping habits
- Rapid breathing
If your child is old enough to express how she feels, she may complain of:
- Body aches
- Not being able to sleep or needing to sleep more
- Decreased appetite
After examining your child, the doctor may order certain tests to determine – or rule out – the cause of fever. The most common tests are urinalysis and blood tests to check for bacterial infections and/or dehydration. A throat culture can diagnose common sore throat conditions such as strep throat. A chest x-ray can help diagnose certain heart, lung, and chest conditions. If the doctor suspects meningitis, she will order a lumbar puncture (spinal tap).
If your child is younger than 3 months old and has a fever greater than 100.4° F, call your doctor immediately. For children older than that, temperatures below 102° F generally do not need to be treated.
For fevers of 102° F or above but less than 105° F, you should call your pediatrician to see if you should bring your child in for a visit. Monitor your child’s appetite, behavior, and sleep. If your child is eating, behaving, and sleeping normally, he probably has a viral infection and the fever will go away on its own in a few days. You can manage the fever with over-the-counter infant or children’s formula acetaminophen or ibuprofen. Never give aspirin to a child under 18, as it can cause a serious brain condition called Reye syndrome.
You might also give your child a bath in lukewarm water to help bring down her temperature. Do not use cold water or alcohol. Make sure your child gets plenty of fluids and rest. Clear fluids without caffeine, such as chicken broth, Pedialyte, ginger ale, and sports drinks, are best for preventing dehydration.
The majority of fevers are caused by a virus. If you take your child to the doctor and he is diagnosed with a viral infection, your doctor will likely advise you to manage the fever with children’s acetaminophen or ibuprofen. Antibiotics do not treat or cure viruses.
However, if your child is diagnosed with a bacterial infection such as an ear infection, sinus infection, strep throat or urinary tract infection, the doctor will prescribe oral antibiotics. Your child might also receive a shot of antibiotics. If your child is vomiting or seriously dehydrated, she might be given medication to control nausea and/or intravenous fluids.
To prevent the viruses and bacteria that cause fever, teach your child proper hygiene:
- Make sure your child washes his hands frequently, especially after going to the bathroom and before eating.
- Teach your child to cough or sneeze into a tissue or her elbow and to use a tissue when wiping her nose.
- Tell your child not to share food, cups, or utensils with other children.
- Use disposable antibacterial wipes and hand sanitizer in public places where soap and water are not available.
Am I at Risk
Young children are most susceptible to fever, especially those in daycare or preschool. Coming in contact with another child who has a viral or bacterial infection is the main risk factor for fever.
Children with high or persistent fevers may experience complications such as:
- Severe dehydration
A small number of children ages 6 months to 5 years may have a fever-induced seizure characterized by a loss of consciousness and shaking of the arms and legs. While this is certainly scary for parents, these seizures almost never have a lasting effect such as brain damage.