The fine art of finding a fever Health: Taking a child's temperature is an important first step toward curing a sickness. Here's a look at the many methods in use today.


Junior is hot. His little cheeks are fiery red. He is crankier than 3-year-olds usually are. He says his head hurts, his tummy hurts, everything hurts.

Your tot is sick, and now you have to take his temperature. And what seems like a simple thing becomes a battle of wits and

nerve and science and math. Your family medical book says you should take the temperature rectally; it's the most accurate. You look doubtfully at Junior, who is whining, "I don waaaaanna take my temperature."

You know an oral temp won't work. He's too young to sit still and keep it under his tongue.

You own one of those fancy ear thermometers, but Junior is also complaining that his ears hurt. (His foot, however, works just fine as you discover when he kicks you as you try to insert it.)

You could put the thermometer in his armpit, called the axillary method. But your mother-in-law told you it was horribly &r; inaccurate.

What to do?

Taking someone's temperature or your own has become more complicated these days with the variety of thermometers on the market. What's more, the accuracy of the reading varies according to the instrument you use, where you place the thermometer, the time of day you take the reading and even the age of the person.

But it's important to surmount those factors because doctors need accurate information, says Dr. Michael Bryant of Children's Hospital Los Angeles.

"It's invaluable to teach proper techniques and how to read the thermometer. The patient's history is what we rely on plus the physical exam. The more reliable that information is, the better off we are."

A rectal reading is the most accurate because there are fewer confounding factors. According to a new study, however, a rectal temperature can vary depending on how far the thermometer is inserted. The thermometer (a rectal thermometer has a rounded bulb, while an oral thermometer has an elongated bulb) should be inserted about eight-tenths of an inch. Just by increasing the depth a bit, to about one inch, the temperature could be two degrees higher, says Dr. Frank Shann, an Australian doctor whose study was published recently in the Archives of Pediatrics and Adolescent Medicine.

An oral temperature is a good method, too, once a child is old enough to hold a thermometer properly about age 7.

But other methods, such as ear and skin strip thermometers, have problems. Skin strips are placed on the forehead or under the armpit and change colors in response to heat. In his study, Dr. Shann found that the strips work quickly but are not as accurate. Readings can vary from moisture or sweat on the skin. And, Dr. Bryant says, ear thermometers have to be inserted properly to work well.

"Kids are very reluctant to allow you to put anything in their ear," he says. "They are afraid, and the parents get reticent and may not do it correctly. You also need to get a very good seal (putting the thermometer far enough into the ear) to get an accurate temperature."

Doctors generally don't like the axillary method, either, although this is probably what parents of children ages 2 through 7 rely on the most, considering the lack of enthusiasm kiddies in this age range have for oral and rectal methods.

"The axillary reading can vary tremendously according to the ambient temperature of the room, how it's placed under the arm, how long it's left there. I don't prefer it," Dr. Bryant says.

Tips on taking a child's temperature

Infant Ideal method of temperature-taking: rectal. A temperature less than 100.4 degrees Fahrenheit rectal is not a fever, but anything more than that should be reported to a doctor. Here's how: Lubricate the bulbous tip of a rectal thermometer with petroleum jelly or cold cream. Put infant on stomach. Insert thermometer slightly less than an inch (eight-tenths). Hold in place for two minutes. Subtract one degree to convert to oral temperature. Child younger than 7 Ideal method of temperature-taking: rectal Optional method: armpit (axillary) Here's how: Tuck a glass mercury or electronic digital thermometer in the armpit and have the child fold his hands across his chest. Hold for three minutes. Add 1.8 degrees Fahrenheit to convert to rectal. Less than 100 degrees Fahrenheit oral is not a fever. For brain damage to occur, fever must be 105 to 107 degrees Fahrenheit for several hours. Age 7 and older Ideal method of temperature-taking: oral The normal temperature of older children and adults is usually not more than 99.9 degrees Fahrenheit. Here's how: Hold thermometer under tongue with lips closed for three minutes. Don't talk or bite. Don't take temperature after smoking, bathing or showering or eating hot or cold food. : The Mayo Clinic Family Health Book (William Morrow & Co., 1990), the Center for Corporate Health, Archives of Pediatrics and Adolescent Medicine.

Pub Date: 3/12/96

Copyright © 2019, The Baltimore Sun, a Baltimore Sun Media Group publication | Place an Ad