Health Guide: Normal Body Temperatures for Babies and Adults

When we talk of normal body temperature, the figure that comes to one’s mind is 37°C. This number is an average and may vary slightly to be higher or lower by up to 0.6°C.^1a,b

With the recent global pandemic, the thought of having a temperature that is higher than 37°C may be worrying.

However, at different stages of life, the average body temperature varies. Below are guidelines for the average body temperature of babies, children, adults, and the elderly:^1c

• Babies and children - In babies and children, the average body temperature ranges from 36.6°C to 37.2°C
• Adults - Among adults, the average body temperature ranges from 36.1°C to 37.2°C
• Adults over age 65 - In older adults, the average body temperature is lower than 37°C

What causes changes in body temperature?^1d,2a

• Time of the day - A fever in the early morning might occur at a lower temperature than a fever that appears later in the day
• Age - Younger people tend to have higher average body temperatures. This is because our ability to regulate body temperature decreases with age
• Physical Activity
• Certain foods or drinks
• Hormonal changes in women – Body temperature may rise or fall at different points during a woman’s menstrual cycle
• How you take your temperature - Armpit readings can be up to an entire degree lower than a reading from the mouth. And temperature readings from the mouth are often lower than readings from the ear or rectum
• Viral or bacterial infections
• Heat exhaustion
• Certain inflammatory conditions such as rheumatoid arthritis — inflammation of the lining of your joints (synovium)
• A malignant tumour
• Some medications - such as antibiotics and medicines used to treat high blood pressure or seizures
• Some immunisations - such as the diphtheria, tetanus, and acellular pertussis (DTaP) or the pneumococcal vaccine

What is a fever?^3d,g,h

• Fever is a normal response of the body to illness that facilitates and accelerates recovery
• Fever is defined as a body temperature that is more or equal to 38°C. Fever is frequently a cause for concern among parents and doctors
• In children, it is more accurate to measure body temperature in the ear, or in the armpit.
• Fever is not harmful. However, fever in a child younger than 3 months of age should be further investigated by your doctor

How to treat a fever?

• Medicines to relieve pain and fever are mostly given to relieve the discomfort for you and your child. If your child has a fever, relieving discomfort enables the child to eat better, to prevent dehydration and to reduce irritability^3a,4a
• Paracetamol and ibuprofen may be given to relieve pain and fever. Aspirin should not be given to children or adolescents younger than 12 years of age, as it increases the risk of a rare but serious condition called Reyes syndrome^3a,i
• For parents and caregivers, anxiety and fear manifest and this results in the child receiving more medicine than is needed to adequately treat a fever^5b
• For pain and fever medicine to work most effectively, it is very important to take or give the medication at the prescribed dose^5g,h
• Taking or giving too much medicine may result in unwanted side-effects or toxicity and taking or giving too little will hamper the effect of the medicine^5h

When to see a doctor?

Most of the time, rest is the best medicine. However, it is time for adults to call the doctor if: ^1e

• You have a temperature over 39.4°C
• You have had a fever for more than 3 days straight
• Your fever is accompanied by symptoms such as:
  • Vomiting
  • Headache
  • Chestpain
  • A stiffneck
  • A rash
  • Swelling in the throat
  • Difficulty breathing

With babies and younger children, call your paediatrician if:^1e,3d,e

• If you are in any way concerned about your child
• Your baby is less than 3 months old and has a fever
• If the fever continues for more than 48 hours
• Your baby is between 3 months and 3 years old and has a temperature of 38.9°C
• Your child is 3 years or older and has a temperature of 39.4°C
• If your child cries inconsolably and cannot calm down, or cries when you touch him or her If your child stops eating or drinking
• If your child’s fever is accompanied by other symptoms such as:
  • A stiff neck or severe headache
  • A sore throat
  • Ear pain
  • An unexplained rash
  • Repeated vomiting and diarrhea
  • Signs of dehydration

For more information, refer to your healthcare provider.