A fever is an abnormally elevated body temperature. It is often a sign of the body’s defense system working in overdrive to fight off an infection. There are many different causes of fevers, and they can be associated with a number of symptoms depending on their cause.
For an infant, the best and most effective way to measure a temperature is rectally. This is done by inserting a thermometer into the anus. If the temperature on the thermometer reads 38⁰C (100.4⁰F) or higher, that is considered a fever. The most common way of measuring temperature in children is by mouth, or oral temperature. A reading above 37.8⁰C (100⁰F) or high is a fever. Other ways of measuring temperature include in the armpit (axillary temperature). A reading above 37.2⁰C (99⁰F) is a fever. Lastly, temperature measured by the ear (tympanic temperature) is a fever if it is 37.5⁰C (99.5⁰F) or higher.
The American Academy of Pediatrics suggests that the best measure of temperature in infants and children is axillary. This is due to a slightly increased risk of rectal perforation when taking your child’s temperature rectally.
While there are many different causes of fevers, the most common culprit in children is an infection, including but not limited to:
Other causes of fever in children include:
Depending on the cause of the fever, there may be associated signs and symptoms.
Infants who have a fever may be more fussy than normal, be irritable, quiet, or tired. They may also be warm to the touch, or may have changes in sleeping and eating habits. About 5% of children aged 6 months to 6 years may experience seizures related to their fever. A seizure is convulsion of the body which can cause loss of consciousness. These body shakes can last as short as seconds, or as long as 15 minutes. Although these seizures can be very scary for parents, these seizures are usually short and harmless. These seizures at not related to any type of seizure disorder like epilepsy. They are simply a result of the fever. Most children grow out of these febrile seizures.
Children with a fever may complain of being too warm, or too cold, headaches, having trouble sleeping, may sleep more than normal, have a decreased appetite, or body aches.
Fever can be treated at home by lightly dressing your child, and drinking lots of fluids. Medications like acetaminophen (Tylenol) or ibuprophen (Advil, Motrin) can be used to help reduce your child’s fever and to help them feel better. Do NOT give your child aspirin! And depending on the cause of the fever, there may be other helpful medications, but be sure to check with your doctor or nurse practitioner for assessment.
There are many other conditions that can cause a fever in infants and children. The intensity, or the higher the fever does not necessarily mean that the infection is worse. It’s best to see your doctor or nurse practitioner if your infant or child has a fever to assess for other symptoms, and to narrow down a possible cause of their fever.
Make sure to see your doctor or nurse practitioner immediately if your child has a fever and:
If your doctor or nurse practitioner is not available, visit your nearest emergency room.
– Dr. Christina Cesareo and Dr. G Paul Dempsey