What is a fever?

A fever is when the body temperature rises above 37.2 degrees Celsius. The normal body temperature is between 36 and 37 degrees Celsius.

What causes it?

Fever is generally caused by a viral or bacterial infection, although immunisation can sometimes cause mild fever in children and adults. Fever is the body's way of fighting infection.

How do I take a temperature?

• shake down the mercury in the thermometer, so that it falls below the 35 degree Celsius line (or press reset on a digital thermometer)
• place the silver tip or thin end of the thermometer high in the armpit of a young child or in the mouth, under the tongue of an older child or adult. It is important that the thermometer remains in the right place.
• leave in place for at least two minutes
• read the thermometer by gently rotating it between your thumb and forefinger. The temperature is measured by looking at the level of the silver bar which runs up the middle of the thermometer. If you cannot read this type of thermometer, you can buy a thermometer which has a digital read-out on the side and which beeps when it is time to be read
• wipe the thermometer with antiseptic or lukewarm soapy water. Do not use hot water or you will break the thermometer.

How is fever treated?

Visit your doctor to find out what is causing the fever. Follow his or her advice carefully about home care, changes in the person's condition and what to do if they get worse after hours. If the doctor can find the cause of the infection, antibiotics may be prescribed. Be aware that many infections are caused by a virus, in which case treatment with antibiotics is ineffective.

Do not let the person with a fever wear too many clothes or use too many blankets. If they are shaking and feel cold, cover them up until the shakes stop, then promptly remove the blankets.

• Do not use hot water bottles or electric blankets. Shaking is the body's way of cooling down when it is very hot.
• Make sure the room temperature is comfortable.
• Open a window for ventilation but avoid draughts.
• Drink plenty of clear fluids - aim for one glass every hour.
• Ice-blocks are useful for children.
• A lukewarm flannel-bath can be refreshing.
• Fill a large basin or bucket with lukewarm water.
• Using a flannel, wash the face, hands and neck.
• Change the bed linen and clothing regularly.
• Take medicine to reduce the fever and symptoms.
• In children give paracetamol, as directed on the bottle, every four hours until the temperature settles.
• Adults should take aspirin or paracetamol for relief.
• If the temperature is very high, this type of medicine will probably cause the person to sweat profusely. This is normal.

Take or return the child or adult to the doctor if they have:

• a severe headache or neck pain
• pain anywhere in the body (especially the ears)
• not had anything to drink for 10 hours or are constantly vomiting
• say that light hurts their eyes
• not improved after 48 hours
• difficulty waking up
• if they look like they are getting sicker or you feel really worried.

For further information and support talk to your doctor or practice nurse or talk to your local pharmacist.

Written by Anna Mickell RCpN. Reviewed by everybody.