Fever
What is a fever?
A fever is an increased body temperature of 37.4°C or above. It is the body's natural response when fighting an infection.
In children, it is common to see high temperatures of up to 40°C. Having a higher temperature does not indicate a more severe illness. However, for infants and toddlers, a fever may suggest a serious infection.
What are the symptoms of a fever?
When you have a fever, your body temperature is higher than 37.4°C. Don’t rely on touch to assess a temperature. Use a thermometer.
As a child, you may also experience:
- Irritability
- Lethargy
- Longer sleeping time
- Febrile fits during a sudden rise in temperature, or before a fever is detected.
- Reduced appetite for food and drinks
- Shivers
As an adult, you may also experience:
- Headaches
- Body aches
- Hot, flushed face
- Loss of appetite
- Sweating or weakness
- Shivers
When to visit the UCC?
Visit our 24-Hour Urgent Care Centre (UCC) if you or your child have the following symptoms or medical history:
Child
Your young infant (below 3 months old) has a temperature of 38°C or more, or your child displays the following symptoms:
- A temperature exceeding 41°C
- Drowsiness or increased lethargy
- Fever for a few days with no other symptoms
- Extremely irritability or inconsolability despite efforts to lower the fever
- Recurrent vomiting, with a stiff neck or severe headache
- Refusal to drink fluids or unable to pass enough urine
- Severe pain over any part of the body
- Red lips, red eyes or a rash
- Hard or fast breathing
- Febrile fit or seizures
- Smelly urine
Adult
You had:
- A seizure or fits, coupled with fever
- Surgery or a medical procedure recently
You are:
- Pregnant
- Coughing up blood
- Struggling to breathe
- Undergoing chemotherapy with an oral temperature that exceeds 38ºC for more than 1 hour
- Taking steroids and medicines used to prevent rejection after an organ transplant
You have:
- Rashes
- Infections often
- Diabetes, heart disease, cancer, lupus, or sickle cell anaemia
- Recently been to Africa, Asia, Latin America, or the Middle East
- Severe pain in the belly, back, or sides
- Severe headache or neck pain
- Severe vomiting or diarrhoea
- Seizure or confusion
- Severe chest pain
What causes fever?
In children, fever is usually caused by the following.
- Viral infections such as colds, flus, gastroenteritis or dengue fever.
- Bacterial infections such as ear infections, pneumonia or urinary tract infections.
A fever might be also be caused by:
- Heat exhaustion
- Certain inflammatory conditions
- Certain drugs and medications
- Malignant tumours
- Vaccinations
This page has been reviewed by our medical content reviewers.
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