A fever is a temporary rise in body temperature. It’s not considered an illness on its own, but rather a symptom that can be caused by many different conditions. Elevated body temperature can be a ...

If you are an adult with a fever over 104 F (40 C), call your healthcare provider. If it is over 105 F (40.5 C), go to your nearest emergency room. For a newborn, a fever of 100.4 F (38 C) requires ...