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"What causes fevers to persist?"

ZocdocAnswersWhat causes fevers to persist?


My older brother has had a fever for more than a day. That seems pretty strange, because I think mine never last longer than an evening. Is he really sick? My dad says it's no big deal, but I'll take him to the hospital if this is a sign that something's really wrong.


Anytime you are concerned about a family member's health it is never a bad idea to call his or her primary care physician (either family doctor or pediatrician). They will be able to give you direction on what the next best step is. This way you will know whether or not to take your brother to the hospital. Fevers are very general sign of a person's immune system becoming activated. This is why people develop fevers when they acquire an infection. A fever's length depends on how long the infection, or other process that is causing immune cell activation lasts. Fevers that last more than 1 day usually don't mean anything specific, other than whatever illness is going on is still active. People usually have them for as long as they are sick. For example if your brother has the flu, then his fever may last for a few days. If he has a viral upper respiratory tract infection, the fever usually only lasts a day. It is true that sometimes a prolonged fever is the sign of a serious illness that requires hospitalization. Unfortunately, only your brother's doctor make the decision about whether his illness requires a trip to the hospital. Good luck, I hope he feels better.

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