A child's body temperature is usually between about 36.5°C and 37.5°C but varies from child to child and with age. A child is generally classed as having a fever if his or her body temperature is 38°C or above.
Fever isn't an illness in itself but is usually caused by a virus or bacterial infection. Fever is thought to be part of your body's natural response to an infection.
Fevers are common in young children. They are usually caused by viral infections and clear up without treatment. However, a fever can occasionally be a sign of a more serious illness, such as a severe bacterial infection of the blood (septicaemia), urinary tract infection, pneumonia or meningitis.
If your child has a fever, he or she will have a body temperature of 38°C or above. As well as having a high temperature, your child may also:
In some children, a fever can lead to seizures (fits) called febrile convulsions. During a febrile convulsion, part or all of your child's body may shake and twitch and your child’s eyes may roll back in his or her head. He or she may lose consciousness, and may be confused immediately afterwards. Febrile convulsions don’t usually last for longer than a couple of minutes and some last only a few seconds, but others can continue for up to 15 minutes.
Although febrile convulsions can be frightening, there is no evidence to suggest that they cause brain damage and your child is likely to make a full recovery. See our frequently asked questions for more information.
Fever can occasionally be a sign of a serious infection. Take your child to hospital or contact your GP immediately if your child:
It’s also important to contact your GP if your child’s fever:
Most fevers are caused by common viral infections, such as the common cold or flu, and go away on their own. Sometimes a fever can be caused by something more severe, such as an ear, bladder or kidney infection. Rarely, a fever can be a sign of a serious illness, such as meningitis or septicaemia.
Very rarely, children may develop a fever as a symptom of a condition other than an infection. For example, certain autoimmune disorders or cancers may cause a fever. If this is what is causing your child’s fever, it’s likely to last for longer than one associated with an infection.
Fever can also be a side-effect of some childhood immunisations. See our frequently asked questions for more information.
Depending on your child’s age, you can check his or her temperature from the ear, mouth (only if your child is over five) or armpit. You will need to take your child's temperature from under the armpit if your he or she is under the age of five, but bear in mind that these measurements are less accurate as the armpit is slightly cooler.
To take your child’s temperature this way, place the thermometer under his or her armpit, directly against the skin, and hold his or her arm gently against the chest. To take your child’s temperature by mouth, place the thermometer under his or her tongue for two to three minutes. Some digital thermometers will beep when they are ready.
Mercury thermometers are no longer recommended because there is a risk the thermometer could break and release the mercury, which is poisonous, into your child's body.
If your child has a temperature of over 38°C and is unwell, for example, floppy or irritable, contact your GP. This is especially important if your child is aged three months or younger. It’s also important to contact your GP if your child has any of the symptoms of a serious infection, even if his or her temperature isn’t particularly higher than usual.
Your GP will ask about your child's symptoms and can advise whether your child needs to be examined. If so, he or she will take your child’s temperature and measure his or her breathing and heart rate. Your GP will also ask about your child’s medical history. It may help if you keep a record of your child's temperature and other symptoms so that you can give clear information to your GP.
There is likely to be an obvious cause for your child’s fever, so he or she may not need to have further tests. However, if your child’s fever lasts longer than a few days and the cause isn’t clear, your GP may also take a urine and/or blood sample. If your GP is concerned about your child’s symptoms, he or she may be referred to a paediatrician (a doctor who specialises in children’s health).
Usually, your child's fever will be caused by a viral infection and will get better on its own. Monitor your child's condition by keeping an eye on his or her behaviour and whether he or she has any symptoms other than a fever. You don’t need to keep checking your child’s temperature if he or she is otherwise well, but if your child has a fever that lasts for more than five days, contact your GP.
Many parents and carers spend a lot of time trying to bring down their child’s fever. However, a fever is part of the body’s natural response to infection and can often be left untreated provided your child isn’t distressed.
Children who have a fever are often at risk of dehydration, so try to encourage him or her to drink to prevent this from happening as it can lead to more serious problems. As a guide, your child's urine should be pale yellow – if it's darker, or your child passes urine less frequently, he or she may need to drink more fluids. See our frequently asked questions for more information.
Your child is likely to feel more comfortable if you dress him or her in lightweight clothes and reduce the number of bedclothes used to cover him or her. This will enable your child to lose heat more easily. Although it’s important that your child doesn’t overheat, take care to ensure that he or she isn’t underdressed either. Don’t actively try to cool your child, for example with sponging or a cool bath, as this isn’t effective and may cause him or her to start shivering.
Keep your child away from school or nursery while he or she has a fever.
If your child is over three months old and is distressed by the fever, you can try giving him or her paracetamol or ibuprofen. This may help to make your child feel better.
Make sure you keep a note of how much paracetamol or ibuprofen your child has had and be careful not to exceed the safe dose. It’s important that you don’t give your child paracetamol and ibuprofen together but if the first medicine you try doesn’t help, you can try the other one later.
You can buy medicines that are suitable for children from a pharmacy without a prescription. Always read the patient information leaflet that comes with your child’s medicine and if you have any questions, ask your pharmacist for advice.
If your child has a bacterial infection, your GP may prescribe a course of antibiotics.
Produced by Polly Kerr, Bupa Health Information Team, February 2013.
For answers to frequently asked questions on this topic, see FAQs.
For sources and links to further information, see Resources.
This information was published by Bupa's Health Information Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals. Photos are only for illustrative purposes and do not reflect every presentation of a condition. The content is intended only for general information and does not replace the need for personal advice from a qualified health professional. For more details on how we produce our content and its sources, visit the about our health information page.
Award winning UK
Bupa Health Cash Back can help with everyday costs like prescription expenses. Call 0500 000 125 quoting ref. 3948 for more information.
Bupa Health Finder
Find health information and more while on the move with our free Bupa Health Finder app.