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    Fevers and Everything a Mom Should Know

    Fevers and Everything a Mom Should Know

    Fevers

    ​The most frequent causes of fever vary with the season. During the summer the source is usually a gastrointestinal virus (stomach bug) that causes diarrhea and vomiting. The winter brings respiratory viruses, like colds, that are usually the culprit. In either case, hydration is always more of a concern than fever. High temperature is simply a symptom of illness. But first, what is a fever and how did we come up the magic number of 98.6?​

    In the 1860s, a guy by the name of Carl Wunderlich measured the temperatures of thousands of people, thousands of times and came up with the average: 98.6. Some have argued that this number wasn’t very accurate to start with, but that is the number everyone uses. Our body temperature normally varies throughout the day, sometimes by as much as two to three degrees. 

    For medical purposes, a fever is defined as a temperature of at least 100.4 degrees. A rectal temperature is the most accurate method for children under two. For kids two and older, oral temperature is preferred. There are several other methods available, but they may not be as reliable or accurate.

    Once the temperature has been measured, and the child
    has a fever, now what? When I get a call from a worried parent, I am most concerned about why their child has a fever. Do they have a simple cold or other virus, or do they have something more that may require
    treatment? The best way to decide is to observe how the child is acting: are they still playful when the fever is down and are they drinking enough to maintain hydration? It is also important for the doctor to know of any other medical problems the child is treated for, such as asthma, and the medications they take.

    It is true that with infants​ under two months of age, doctors take fevers more seriously. This is because fever is often the only sign of a serious infection in young infants. If a newborn gets a fever, even if she looks perfectly well, she will require a very thorough workup to look for possible sources of infection. Once this critical newborn time has passed, a fever is no longer as concerning.

    I admit from first hand experience, that fevers can be scary for parents to manage. Our child is sick and uncomfortable. We probably have heard from other parents or relatives about the perceived dangers of fevers, so we also become afraid of what a fever could be doing to our now sick and whiny child. The biggest fear I have heard parents express is that if the fever is not brought down immediately, or if the fever gets too high, there is risk of brain damage.

    Temperature is very closely monitored and controlled by our bodies. We have a thermostat deep in the brain, called the hypothalamus, which controls core body temperature. When a child gets sick, whether caused by a virus or bacteria, one of the defenses of the body is to raise the temperature a few degrees by resetting the thermostat. This causes the child to feel cold, to shiver and conserve heat. To the parent, the child feels hot. Medications are effective for lowering the temperature, but only by one to two degrees. Medications do not reset the thermostat though, so as soon as the medication wears off after a few hours, the temperature will go back up.

    Once the body decides it has been long enough, it will reset the thermostat back to normal and the fever will break. Now the child will feel hot and sweaty, kick off the blankets and start to feel a lot better,
    even without treatment. It is also important to realize that even if a fever is never treated, once the temperature reaches the new, higher preset point, the fever will level off. It will not keep rising higher and higher. The body also will not cause a fever to be so high as to cause brain damage. Temperatures up to 105, or even 106, have never been shown to cause any damage to the brain. This is different from hyperthermia when the body thermostat is not in control.


    Another common fear is that if we do not treat the fever, the child will have a seizure. The truth is that only a very small percentage of children are predisposed to a seizure related to fevers. When it does happen, the seizure is usually the first sign of illness: the child has a seizure, then she is later diagnosed with a fever also. Treating a child that already has a fever with acetaminophen or ibuprofen for the purpose of preventing a seizure, has shown to be more anxiety provoking for the parent and really does not change the risk of seizure.

    The best advice I could give is do not treat the fever, treat the child! I would never wake anyone who is sleeping just to medicate a fever. The most important reason (maybe the only reason) to treat a fever is for the comfort of the child. If the child is happy, playing and otherwise seems okay, do not bother treating. Let the body do its thing and fight the infection. It is perfectly acceptable to let it burn. If, on the other hand, the fever is causing the child to be very miserable and uncomfortable, go ahead and treat.

    Acetaminophen and ibuprofen are two medications that have been in use for a very long time, and found to be safe and effective for treatment of fevers. I prefer ibuprofen because it lasts longer and has good anti-inflammatory effects, which are helpful especially for illnesses like ear infections.
    But remember that if the child is less than two months old, call the doctor.