Fever phobia is one of the hardest “medical misunderstandings” I encounter. A seminal paper published in 1980 found that parents thought fever could harm their child, cause brain damage, convulsions (which I assume means seizures…), hearing loss, and even blindness. But that was 1980, right? Wrong. I still get questions like, “At what temperature should we go to the ER,” “What temperature causes brain damage/seizures/etc,” and my absolute favorite, “At what temperature does the brain boil?”
First of all, I think the medical community as a whole is partially responsible for this phobia. One of the first questions I ask parents is, “Does your child have a fever?” Discharge instructions nearly always say contact someone if you develop a fever. One of the first vital signs we check is temperature, and then we immediately medicate it. I get it. We put a lot of importance on body temperature, and we don’t always spend a lot of time educating about fever.
So, let me shed some light on the subject.
The muscles and liver generate the majority of body heat, and the lungs and skin release the majority of body heat. The hypothalamus (part of the brain) is the overseer of the process. The average, normal body temperature is 99.9 degrees. Not 98.6, which is from an outdated study from the 19th century. Normal body temperature varies with age, time of the day, level of activity, and phase of the menstrual cycle, among other factors. Infants and young children generally have higher temperatures than older children and adults. The lowest body temperature is usually in the morning, and the highest temperature is usually at night. This temperature cycle is even there when you have a fever.
Fever is an abnormal body temperature elevation that happens in response to infection, and is controlled by the central nervous system. Germs and immune system cells both release chemicals that tell the brain to raise its “set point.” The hypothalamus goes from being comfortable at 99.9 (previously known as 98.6), to something higher than 100.4. At this new, hotter brain set point, the rest of the body is tricked into thinking it’s cold. So, blood vessels get smaller to prevent heat loss, and muscles shiver to generate heat. Eventually, all of this heat saving and generating heats the body up.
Fever slows germs down, and boosts the immune system. Viruses and bacteria don’t grow and reproduce well at elevated body temperatures, and the immune system fighter cells function better at elevated body temperatures.
The tipping point seems to be 104 degrees. Fever is uncomfortable, and it also increases the demands on the respiratory and cardiovascular systems. At 104 or higher, the benefits no longer outweigh the stressors.
The Takeaways, for otherwise healthy children:
- Fever is a normal response of the immune system to infection. It is defined as 100.4 degrees, or higher. Even if you feel your body temperature is lower than average, 100.4 is still the cutoff.
- It is a sign of an underlying illness, is not harmful, and is not cause for alarm. Fever is just one piece of the whole puzzle.
- Not every fever requires acetaminophen and/or ibuprofen. It is more important to treat a behavior than it is to treat a number on a thermometer. If your child is uncomfortable, treat the discomfort. If your child is slower than normal, but otherwise fine, please don’t give him medications just because a thermometer says he has a fever.
- Height of the fever, or whether the temperature goes down after giving medications does not tell me if a virus or bacteria caused the illness.
- You do not need to wake your child to give her medications, and you definitely don’t need to check her temperature every hour. Just observe. If she’s uncomfortable, then do something.
I know fever is scary when it’s your own child. Believe me. This is my job, and I still freak out a little if one of my boys has a fever. Sometimes just reframing something scary makes it more manageable. But, the pediatric experts at KidMed are here if you need us.