When Should I Call the Doctor? · infant younger than 3 months old with a rectal temperature of °F (38°C) or higher · older child with a temperature of higher. A fever is a high temperature. As a general rule, in children a temperature over 38C is a fever. Find out how to check if your child has a high temperature. There's a lot you can do to make them feel better. Put a cool compress on their head and keep their room at a moderate temperature -- not too. A fever is defined by most healthcare providers as a temperature of °F (38°C) and higher when taken rectally. The body has several ways to maintain normal. So what is a fever? Fever is defined as a temperature over F ( C). Normal body temperature is F (37 C). Everyone's body. This is called fever phobia. In fact, fevers are harmless and often helpful. Let these facts help you better understand fever. MYTH. My child. Is this your child's symptom? An abnormal high body temperature; Fever is the only symptom. Your child has a true fever if: Rectal (Bottom), Ear or Forehead. A fever is a high temperature. As a general rule, in children a temperature over C (F) is a fever. Learn about its causes and treatment in children. Your child has a fever when their temperature reads above 38°C on a thermometer. Your child may also be: unwell and hot to touch; irritable or crying; more. Have a Fever? When to Call Your Pediatrician · If your child is under three months old, any fever should be addressed. · For children ages three.