Fever in Children and Teens

Fevers are very common in children. They are usually a sign that the body is trying to fight an infection. The normal temperature of the body is 98.6F, or 37C. Your child's temperature may vary during the day and may increase a little when he's bundled up or very active. Generally, doctors say that there is a fever when the temperature is greater than or equal to 100.4F, or 38C. Use a digital thermometer to take your child's temperature; never use a glass mercury thermometer. Most children aged three years and older can hold a thermometer under their tongue. If your child is younger than that, or you're having difficulty with the oral method, talk to your doctor about the best way to take his temperature.
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