The normal temperature inside your child’s body is usually around 37 degrees Celsius. Your child has a mild fever if their temperature is higher than 38 degrees Celsius. A high fever usually means more than 39 degrees Celsius.
Fever by itself does not tell you whether your child is seriously sick.
If your child is miserable and seems unwell, and feels hot, you can use a thermometer to take their temperature if you want to. It is not really necessary to do this if your child seems well.
The number on the thermometer cannot tell you:
The most common cause of a fever in a child is a viral infection. A bacterial infection is a less common but more serious cause.
The body’s natural reaction to infection with a virus or bacteria is to raise the temperature inside the body. This helps to kill the infection.
Other causes of high body temperature include:
Fever is a normal way for a child to fight an infection. Being hot may make your child feel unhappy or uncomfortable, but the high temperature is very unlikely to cause any long-term problems.
Some children have convulsions when they have fevers. These look very worrying, but even these febrile convulsions are very unlikely to cause long-term problems.
See Febrile convulsions on this website.
If you are worried about your child, whether or not there is a fever, you should take them to see a doctor.
If your child has already seen a doctor but they are getting worse, you should take them back for another check.
Call Healthline on 0800 611 116 if you are unsure what you should do.
Dial 111 within New Zealand (use the appropriate emergency number in other countries) and ask for urgent medical help if your child:
You should see a doctor urgently if your child with a fever:
You should see a doctor if your child with a fever:
You can look after your child with a fever at home if they:
Tell your doctor if your child:
Young babies (less than 3 months old) need a different and more cautious approach:
Babies need to be kept warm - but they can get too hot if they are wrapped in too many layers when they are in a warm place. A good guide is to dress your baby in one more layer than you are comfortable wearing in the same environment.
Undress your child so that they are just wearing a single layer (for example, a singlet and pants). Make sure the room is not too hot or too cold. These are the best and most comfortable ways to bring your child’s temperature down. Putting your child in the bath or shower to cool them is not recommended.
Your child is their own best guide to the level of activity that you allow. They may need extra rest or they may want to play.
Encourage them to drink fluids and eat healthy small meals.