A fever is a body temperature of 38°C (100.4°F) or higher. It is usually a sign that the body is fighting an infection, but in young babies it can be a sign of serious illness and needs prompt medical advice.
Key takeaways
- Under 3 months: any temperature of 38°C or higher needs urgent medical advice.
- 3 to 6 months: 39°C or higher needs urgent medical advice.
- How your child looks and behaves matters more than the exact number.
What you can do
- Offer plenty of feeds or fluids.
- Dress your baby in light clothing; do not bundle them up or sponge them with cold water.
- Use age-appropriate fever medicine only as advised on the label or by your doctor.
When to talk to your doctor
Call your local emergency number if your child has a fit, a rash that does not fade when you press a glass on it, a stiff neck, difficulty breathing, blue, grey or very pale skin or lips, or is very hard to wake. Get urgent advice for babies under 3 months with 38°C or more, and 3 to 6 months with 39°C or more.
Frequently asked questions
No. Teething may cause a slightly raised temperature, but a fever of 38°C or more has another cause.