Why is Fever Thresholds Different for Babies and Adults?

Why is Fever Thresholds Different for Babies and Adults?

By Margaret Gaia

It is an age old question for parents, and quite confusion to some extent.  It is said that the human body is a balanced temperature at 98.6 degrees, however with a baby, it is important to recognize that a fever is defined at 100.4 degrees.    Some say this is different because the of the more mature body’s ability to detect and fight disease.  Others say it is simply the inability of the baby to communicate that something is wrong, and fight off the disease all together.   Dr. Spock says, “Babies don’t control body temperature as well as older children.”  This leads us to believe that as the body matures, the body controls temperature, therefore decreasing the degrees which define an adult fever at anything over 98.6 degrees.  As a parent, simply understanding this answer is not enough, being prepared for it is more important.   For example, understanding how to check your baby’s temperature, what causes fever in babies, and when to worry about the body temperature of your baby.

In regards to checking your baby’s temperature, it is important to note the symptoms of a fever.  Is your child warm, irritable, always cold, diarrhea, vomiting, etc?  When checking your child’s temperature, there are sever ways in today’s world that allows for such an action without an unpleasant experience for your baby such as thermometers which test the child’s forehead by gently rubbing the instrument across the hairline.  Putting the instrument under the forearm is also effective.  In addition there are temperature instruments that are made for the baby’s ear and companies have even gone so far as to make pacifiers which have temperature gauges in a digital format on the front of the pacifier.  It is important to follow a few steps such as:  label your rectal thermometer to make sure it is not used in your child’s mouth, cleanse your child’s instrument under warm water and soap, if you are taking temperature orally make sure to wait 20 minutes after the child eats or drinks anything, never leave your child alone with a thermometer, and make sure to sterilize the thermometer after each use.

It is important for a parent to know when to take a baby’s temperature seriously, as it is a sign of infection in the body which the immune system is attempting to fight.  Somewhere around six months of age the child’s immune system begins to develop and fight infections more efficiently.  Then between the four to nine month growth period, fevers become less of a threat and it may not be necessary to make a phone call to the doctor each time a fever develops in your baby.  Naturally, as a parent, comfort is necessary so if you are concerned, a call to your baby’s physician is always recommended.  Symptoms of a fever in a baby are as follows:  dry mouth, vomiting, loose stool, high pitched crying, no appetite, pale skin, rash, sore throat, stomach problems, problems with breathing and wheezing.

With all this said, why a baby’s fever is different than adults is still the question?  Based on my research, it seems the immune system is the most simplistic differentiation between the two.  At birth, a baby’s immune system is still very dependent on the Mommy.  Any fever indication or degree is a concern and a doctor should be called immediately.   At three months to six month, 101 degrees or higher should be a major concern.  Six months or older the immune system gets stronger therefore the degree of temperature and concern should get higher which is noted at 102 degrees.  A parent should monitor the fever and if it the fever gets higher, call a doctor, if not and the fever breaks on or before two days, no doctor is needed and the immune system is doing its job well.  At six months or older, 103 degrees or higher is the mark where a parent should consult a physician immediately.