Bacterial or viral infections will often cause the body’s defensive cells to release proteins. These proteins act on the temperature regulating control centre of the body, causing body temperature to rise. This results in a fever, a temperature different from normal body temperature. Certain illnesses produce high fevers and must be treated with medication. Any variation in normal body temperature may indicate an illness and your doctor should be consulted.
The best method to determine an individual’s normal temperature is to use the thermometer when the person is feeling well. Record readings twice a day (early morning and late afternoon) and take the average of the two temperatures. This is then considered a personal ‘normal’ body temperature.
Temperature readings vary from person to person. There is no ideal temperature reading. An oral temperature between 36.1°C and 37.8°C is considered ‘normal’. A rectal temperature is generally 0.5°C higher and a temperature taken from under the arm will be on average 0.5°C lower.