Nursing sister Burgie Ireland explains:
The safest way to take a baby’s temperature is with a thermometer tucked under the child’s armpit for one minute. Never put a thermometer into a baby’s mouth or rectum. The best kind of thermomete rto use is digital because these are quite easy to read.
However, thermoreceptor digital thermometers are accurate, non-invasive and easy to use. These sophisticated gadgets measure the temperature of the eardrum and all a parent needs to do is to hold the funnel towards the baby’s ear and wait for the recording. They are more expensive and delicate though and, being electronic, need batteries that maybe flat when you need them most.
Regular glass thermometers (preferably digital) are used tucked into the armpit for one minute. They’re inexpensive and easy to use. Non-digital thermometers have to be held at an angle to read the mercury. I don’t recommend using a rectal thermometer (this has a short, round bulb for the mercury) because, although accurate, it can be tricky (sometimes even dangerous) to push a thermometer into a baby’s rectum. It could traumatise an older child. If you do have a rectal thermometer, only use it under the armpit.
Plastic strip thermometers used on the forehead can only indicate a normal, hot or very hot body temperature, but they don’t give an accurate reading. I have seen a “temperature dummy” but it’s usually difficult to get a sick baby to suck on a dummy for a minute.
Apart from a digital thermometer, the best way to check whether your child is too hot is a kiss on the nape of the neck or the palm of a mother’s hand gently pressed against the child’s forehead.
In terms of a fever, there’s something going on – usually an infection – which raises the body’s temperature up a notch or two in an attempt to destroy it. Babies and children spike (and lose) a temperature very quickly. This is a good thing because it alerts you to the problem. It’s wise knowing your child’s temperature before phoning the doctor with an accurate reading, to make it easier to decide what plan of action to take. This depends on the child’s age, how quickly the temperature is going up, and if there are other symptoms such as vomiting associated with the fever.