A child’s normal body temperature is about 98.6 degrees F, but can also be as low as 97 degrees or as high as 99 degrees. Although core body temps for adults and kids are the same, kids generally spike higher fevers. In addition, temperature can fluctuate throughout the day; higher readings are typical in the late afternoon and early evening, then the body temperature dips at bedtime and reaches its lowest point between midnight and early morning. A child has a fever when her body temperature rises to 100.4 degrees F (38 degrees C) or higher.
Some children will tolerate a low-grade fever (under 102 F) well, remaining active and eating and sleeping normally. More typically, however, fevers cause discomfort and your child will act sick. He may be sweating, shivering, develop a headache and muscle aches, lose his appetite, and become irritable. Feverish babies may fuss more, or seem lethargic. Older children may not be as active or talkative. Depending on the cause of the fever, your child may also have an earache, sore throat, diarrhea, or feel nauseous. Feverish children may also become dehydrated easily and their heart rates and breathing may speed up (i.e. the body uses more energy and loses more fluid).
Rarely, a child with a fever will develop more serious symptoms that require immediate medical attention. These symptoms include:
Neck and back stiffness
If your feverish child is over age 2, check to see if she can bend her head downward so that her chin touches her chest, or if she can bend over and touch her toes. If she cannot, it could be a sign of bacterial meningitis, a serious, life-threatening inflammation of the meninges, the membranes (lining) that enclose the brain and spinal cord. The stiff neck and fever may also be accompanied by a severe headache, vomiting, extreme sleepiness. In babies and children under 2, the classic symptoms are difficult to detect. These children may become very irritable or sleepy, feed poorly, and vomit. As the illness worsens, seizures can occur at any age. Bacterial meningitis is rare now, thanks to the widespread use of the Hib vaccine, but it is serious and can do a lot of damage in a very short time, so all parents should be aware of the symptoms. (Viral meningitis is more common but not nearly as serious.)
Whenever a child has a fever you should keep an eye out for rashes. A variety of different rashes may accompany a fever and are relatively harmless, but one that may be more serious: petechiae, which are tiny bright red spots that do not fade (blanch) when you press on them. These rashes result when blood is leaked into the skin. While this rash mostly occurs as a result of excessive coughing or vomiting, it may, rarely, be a sign of more serious illnesses like meningitis or sepsis, which is an infection in the bloodstream, and requires prompt medical attention.
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