The term ‘fever’ means different things to different people and I prefer to refer to a ‘raised temperature’. Serious diseases such as encephalitis and viral and bacterial meningitis start off with fairly simple symptoms. Take measles, for examples. Measles can kill young children, and if it does not, can leave them with serious side-effects or complications such as hearing and visual defects, learning difficulties and brain damage.

The initial symptoms of measles are similar to those of a cold. A runny nose, a bit of a sniffle, a cough and eventually a sore throat. Temperature also rises to over 38 Celsius (100.4 Fahrenheit). If you think that your child has measles, or if temperatures stays at or goes over 38 Celsius, you should inform your doctor immediately.

If you do not have a clinical thermometer, you cannot determine the child’s temperature! You may notice your child becoming a bit flushed, and may feel warmer than normal to the touch. However, it is far better to be able to measure this accurately. With measles, the temperature starts to drop after a day or two, then increases again as the spots appear and go as high as 40C (104F). You should definitely have contacted a doctor by then, but if you have no thermometer you may not have noticed the increase in temperature.

In many cases the temperature increase is the only indication that your child has more than just a cough and a runny nose. There are various types of thermometer available suitable for children. The old glass type with the kink is not recommended for young children. Digital thermometers are better, though disposable ones in the form of plastics strips with temperature sensitive dots are very useful. One side is self adhesive to stick to the skin under the armpit and the dots change colour at different temperatures. They can be used while the child is asleep and are disposable or re-usable for a certain period of time.

An alternative safe method to this is the ear thermometer which measures the infrared heat emission from the eardrum. An infrared probe is inserted into the ear and the temperature measured. This is safe because the probe is too short to reach the eardrum, and is larger than an infants ear canal. This is the type of system employed in hospitals, and is available for purchase either online or from good pharmacies for from around £30 ($50). Forehead thermometers are also available, and traditional glass rectal thermometers can be used with infants by trained staff.

The second part of this article will give more detail on thermometer types and how they are used, and also discuss ‘normal’ body temperature and its natural fluctuations.