fever; feverish; temperature;
What is a fever?
The normal temperature of your body is between 35.8ºC and 37.4ºC. This is the temperature inside your head, chest and abdomen (called your 'core' temperature. Your feet and hands can be cooler or hotter than this depending on what you are doing or the temperature of the air around you.
You have a fever when your core temperature rises above normal, if it goes above 38ºC. (If your temperature goes below 35.5ºC there could be a serious health problem too but this is pretty rare.)
Having a fever usually shows that your body is fighting some sort of infection.
What causes fever?
- Most fevers in kids are caused by viral infections. Most of these infections are not serious and the fever doesn't last for very long before your body has managed to fight the virus off.
- Bacterial infections, like ear infections or tonsillitis can cause a fever. Sometimes your body can get some help from antibiotics to fight off these infections more quickly, but antibiotics do not help if you have a viral infection.
- Hot weather and too much sun, a hot bath and racing around playing games can all raise your body temperature for a short while but not usually above 38.5ºC.
How you know when you have a fever
You may have a fever if:
- You are feeling really hot and unwell, or one minute you are sweating then you are feeling cold.
- You are vomiting (throwing up)
- You want to lie down and sleep all the time.
- You are feeling really irritable and cross.
- Your skin feels hot to the touch.
- You have a headache and your eyes hurt when you look at bright lights.
- A thermometer shows that your temperature is above normal.
Some young children, under the age of 6 may have convulsions (fits) if their temperature goes up suddenly. Though these can be scary to see they don't harm the child.
For more information about what to do if someone has a convulsion have a look at the section 'How to help your friend' in the topic Epilepsy – having 'fits'.
What to do if you have a fever
- Give your body the chance to fight off the infection by resting and sleeping. Running around or trying to keep on doing your normal things will probably make you feel worse and could make your temperature go higher.
- Drink plenty of water.
- If your parents or carers think it is ok you could take a paracetamol tablet if you have a headache.
- Snuggle down under a light covering that you can throw off if you feel too hot. Your body needs to be able to lose heat through your skin.
- Cold showers or cool baths are not a good idea. They may cool your skin down but then your body has to warm you up again (which could make your temperature even higher) instead of getting on with fighting the infection.
- "Usually when I'm sick my mum gives me chicken soup and makes me stay in bed." (Michael)
- "I just feel sleepy when I have a fever so I go to bed."
- "When I have tonsillitis my head feels all fuzzy and my throat hurts too."
- "I had to go home from school because I had a fever and threw up."
- "I go red when I have a fever and mum sends me to bed."
Dr Kate says
The most important things to do if you have a fever are to rest, have plenty to drink and see a doctor if you are not getting better.
Our topic on Colds and flu may be helpful.
We've provided this information to help you to understand important things about staying healthy and happy. However, if you feel sick or unhappy, it is important to tell your mum or dad, a teacher or another grown-up.