Does a fever always mean your child is seriously ill? Not necessarily, says pediatrician David Hornick, MD. “Many parents think a fever is caused directly by a virus or bacteria, but it’s actually caused by your child’s immune system fighting the germ,” he says.
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Germs don’t like higher temperatures. That’s why your body will send hormones to turn up the heat whenever it fights an infection.
“Fever may not feel friendly, but it’s not necessarily your foe either,” says Dr. Hornick. He says there are many longstanding myths about childhood fevers.
Parents often worry when their children have fevers, but for the following reasons, they don’t necessarily need to be so concerned.
5 common myths about childhood fevers
Here are five myths — and truths — to cool your head about childhood fevers.
Myth #1: The higher the temperature, the more serious the illness.
Truth: A high temperature may indicate a serious illness in teens and adults, but not always in children 12 and under.
“A child’s immune system isn’t as finely tuned, so it attacks every germ at full force.”That’s why children can get a high fever due to a simple cold while adults typically don’t.“More important than the number on the thermometer is how your child is acting,” says Dr. Hornick.
“Make sure he or she is drinking fluids, is somewhat active and feels better after taking appropriate doses of acetaminophen or ibuprofen.”
Myth #2: For true accuracy, only a rectal temperature will do.
Truth: Taking a rectal temperature isn’t always necessary. Rectal temperatures are most accurate, but don’t fret about getting one in older children, advises Dr. Hornick. They are most important in the first six months.
“It’s certainly easier to place the thermometer in your child’s armpit,” he says. “It will stay put as you hold your child.”The armpit (axillary) method is appropriate for any age — and nearly as accurate. So is the oral method, although children usually can’t hold the thermometer under their tongue until age four.
Myth #3: Ear and forehead thermometers are as accurate as digital thermometers.
Truth: Tympanic (ear) and temporal (forehead) thermometers aren’t as reliable as a digital multiuse thermometer. Their readings can be skewed by external temperatures.
A digital multiuse thermometer is the only kind you need. “They’re inexpensive, they’re fast and they’re easy to use,” says Dr. Hornick.
As for pacifier thermometers and forehead strips? “I wouldn’t trust their readings,” says Dr. Hornick. “There isn’t great science to show they are as good as standard oral or axillary methods.”
Myth #4: The only normal temperature is 98.6 degrees.
Truth: 100 degrees may not be a fever. The well-known 98.6 degrees, is a normal temperature taken by mouth. An underarm temperature may be about one degree lower. A rectal temperature may be about one degree higher.
“Your temperature also changes throughout the day, due to hormone cycles,” says Dr. Hornick. “While rectal temperature stays the steadiest, axillary and oral temperatures will be lowest in the morning and about one to two degrees higher in the late afternoon and evening.
”In other words, an oral temperature of 100 degrees just before bedtime may actually be normal. An axillary temperature of 99 degrees in the morning may be the start of a fever.” Anything over 100.4 degrees F is considered a fever.
Myth #5: A high fever will cause seizures.
Truth: Contrary to popular belief, a high fever will not cause seizures. Febrile seizures are not caused by high fever, says Dr. Hornick. They’re caused by a sudden elevation in temperature (even if just increasing from 98.6 to 101 degrees).“You don’t need to reduce fever to prevent seizures,” says Dr. Hornick. “Children can have febrile seizures before you even know they have a fever.”
When fevers are normal
Generally, fevers that last less than five days are not anything to worry about — especially if your child is acting pretty normal (playing, eating and drinking). It’s OK if your child seems a little tired too. A child that is 3 months to 3 years old may have a fever up to 102.5 degrees F (and up to 103 degrees F if he or she is older). These typically are normal signs of fighting an illness.
Also, if a child was recently immunized, a low-grade fever lasting for less than 24 hours generally isn’t a concern.
In many cases it isn’t necessary, but you can treat a fever to help your child feel better.“There is no evidence that reducing a fever will blunt the immune response,” says Dr. Hornick. “So go ahead and treat a fever, just to make your child more comfortable.”
One exception: If your normally healthy child is sleeping soundly with a fever, don’t wake him or her to treat it.
When you should call a doctor
If your child has a fever, these are situations when you should definitely call a doctor:
- For an infant under the age of 3 months with a fever. This can be the only warning sign of a serious illness.
- For a child who has a fever for more then five days. A doctor may want to investigate if there are any underlying causes.
- For fevers of 104 degrees F that doesn’t come down with acetaminophen or ibuprofen within two hours.
- For a child with a fever who isn’t playing, eating or drinking as normal — or who is hard to rouse.
- For a baby with a fever who isn’t wetting three diapers/day.
- For children with a fever who aren’t urinating every eight to 12 hours or at risk for becoming dehydrated.
- For a child recently immunized who has a temperature higher than 102 degrees F or a fever for more than 24 hours.
- Any time you have a concern about your child.