American Academy of Pediatrics

What is a Fever?

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What is fever?

Fever is an elevation of the normal body temperature. Fever is most commonly caused by the body’s response to a viral or bacterial infection, but it can have causes other than infection, such as juvenile idiopathic arthritis, a reaction to a vaccine or medication, or cancer.

What is considered a fever?

For infants and children older than 2 months, a body temperature above 101°F (38.3°C) from any site (axillary, oral, or rectal) is considered meaningfully elevated above normal. For infants younger than 2 months, a body temperature above 100.4°F (38.0°C) is considered meaningfully elevated above normal. These temperature elevations are not necessarily an indication of a significant health problem.

Children’s temperatures may be elevated for a variety of reasons, most of which do not indicate serious illness.

Does fever mean a child is contagious?

  • Children with fever are not always contagious. Noncontagious causes of fever include urinary tract infections, ear infections, and causes unrelated to infections.

  • The most common cause of fever is a viral upper respiratory infection (the common cold). Although the common cold is contagious, it is not particularly harmful to others. Some children have a fever and never develop other symptoms, and the fever resolves by itself. Many infections cause a child to be contagious for several days before a fever develops. Some infections cause a child to remain contagious long after the fever has resolved. Finally, many children spread germs without ever developing a fever or other symptoms.

Is fever harmful to the child?

  • No. Most (virtually all) fevers that occur because of infectious diseases are not harmful. The very high body temperatures in heatstroke are harmful. Children should never be left unattended in a car because the temperature can rise quickly and cause heatstroke (hot, dry, red skin with lethargy) and even death in a young child. Exercising in excessively hot weather or in overheated indoor rooms can also be harmful.

  • Children with fever are usually less active.

  • Children with fever need to drink more to avoid dehydration. Dehydration may occur because fever depletes body fluids, which should be replaced with increased fluid intake.

  • Some young children with fever may have a brief seizure called a febrile seizure. Most brief seizures associated with fever last less than 15 minutes, occur in children younger than 6 years, and are not harmful. They are frightening to witness but do not result in any kind of brain damage. However, a child who has experienced a seizure with fever for the first time should be referred to a pediatric health professional for evaluation. Referral to a pediatric health professional is not needed only if the child’s seizure fits the pattern of a previously identified febrile seizure disorder for that child and the program has been taught by a health professional how to manage a febrile seizure for that child.

  • Fever is one way the body may respond to an infection. When fever develops, all the infection-fighting mechanisms tend to speed up and can help the body fight the infection. Children may have high elevations in body temperature and appear relatively well. Therefore, fever is not a good indication of severity of illness.

  • Behavior is a much more reliable indicator of the significance of illness than the presence and height of fever. However, high elevations in body temperatures can sometimes affect behavior. Children who appear to be moderately ill with a fever should be referred for a medical evaluation.

What are the roles of the teacher/caregiver and the family?

  • Measure a temperature only if a child is acting ill (ie, has a behavior change).

  • If a child who is acting ill has a fever, notify the staff member designated by the child care program or school for decision-making and action related to care of ill children. That person, in turn, should alert the parents/ guardians to pick up the child.

  • Treating the fever is not necessary unless the child is uncomfortable. Evidence suggests fever helps the body fight infection. Acetaminophen (eg, Tylenol) or ibuprofen (eg, Advil, Motrin) may be considered for the child’s comfort if the child feels ill. Generally, there is no rush to reduce a child’s temperature. Aspirin should never be administered to children with fever because of the potential risk of Reye syndrome. Reye syndrome is a serious complication associated with the use of aspirin in someone infected with a viral illness.

  • Any child receiving a medication should have a note from the child’s health professional. The medication bottle should have the child’s name and clear dosing instructions on it. If a child has a fever and behavior change and the requirement for a note and clearly labeled medication is met, the program can administer fever-reducing medication while waiting for parents/legal guardians to come pick up the child.

  • There is no need to cool the child to try to bring down an elevated body temperature. A known exception is if the child’s elevated temperature is not a fever but the result of exposure to extreme heat, often associated with vigorous exercise or an excessively hot environment (heat exhaustion or heatstroke); such instances are medical emergencies that require immediate first aid and health professional care.

  • Infants younger than 4 months with an unexplained fever should be evaluated by a health professional. Any infant younger than 2 months with a temperature above 100.4°F (38.0°C) should get medical attention immediately—within an hour if possible. The fever is not harmful; however, the illness causing it may be serious in infants younger than 2 months.

Exclude from group setting?

Only if

  • Fever is noted in an infant younger than 2 months (60 days).

  • Unexplained fever occurs in an infant who is younger than 4 months.

  • Fever is associated with behavior change or other signs of illness or other conditions that require exclusion (see Conditions Requiring Temporary Exclusion in Chapter 4). The signs of illness are anything (other than the fever) that indicates the child’s condition is different from what is usual when the child is healthy. Exclusion for fever and signs of illness transfers the responsibility from the group care facility to the family to monitor the child.

  • The child is unable to participate and staff members determine they cannot care for the child without compromising their ability to care for the health and safety of the other children in the group.

  • The child has not completed the recommended vaccine series, until it is clear the child does not have a vaccine- preventable illness.

Readmit to group setting?

Yes, when all the following criteria are met:

When exclusion criteria are resolved, the child is able to participate, and staff members determine they can care for the child without compromising their ability to care for the health and safety of the other children in the group

Note: A health professional visit is not required after every exclusion for fever. Requiring exclusion for a specific amount of time for the child who had a fever to be feverfree is not necessary as long as the criteria for readmission listed previously are met.

Adapted from Managing Infectious Diseases in Child Care and Schools: A Quick Reference Guide.

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The information contained in this publication should not be used as a substitute for the medical care and advice of your pediatrician. There may be variations in treatment that your pediatrician may recommend based on individual facts and circumstances.

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