INFECTIONS
Fever
What is a Normal Body Temperature?
The normal average body temperature is 37°C (98.6°F) when measured orally. Your temperature can fluctuate quite a bit through the day depending on what you are doing, what you are wearing and what kind of climate conditions you are exposed to.
Your temperature can be taken in different ways: taken under your tongue (orally), in the ear (tympanic), under the arm (axillary) and rectally. All of these methods can vary by a few decimals:
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Rectum
36.6°C to 37.9°C (97.9°F to 100.2°F)
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Mouth
35.5°C to 37.5°C (95.9°F to 99.5°F)
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Armpit
36.5°C to 37.5°C (97.8°F to 99.5°F)
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Ear
35.8°C to 37.9°C (96.4°F to 100.2°F)
What is a Fever?
A fever is a body temperature that is higher than average. It is a normal response to infection and other illnesses. Fever helps the body fight infection and can be a symptom of illness or disease, either minor or serious. Fever itself is not a disease but a sign that your body is fighting something.
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Ear or rectal temperature:
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Fever: 38°C (100.4°F) to 39.9°C (103.9°F)
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High fever: 40°C (104°F) and higher
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Oral or armpit temperature:
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Fever: 37.6°C (99.7°F) to 39.4°C (102.9°F)
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High fever: 39.8°C (103.6°F) and higher
What Causes a Fever?
Viral infections like those that cause colds and flu are one of the most common causes of fever. Fevers can also be caused by bacterial infections like a urinary tract infection (bladder infection), pneumonia or an ear infection.
Fevers can also be caused by other processes inside your body such as inflammation, allergic reaction, cancer or autoimmune disorders. You can also get a fever from being too hot, like when you work too long in the hot sun. Some medications can cause fevers and sometimes fever can be a sign of hormonal problems.
Treating a Fever
Fever is a symptom of something else going on in the body. Most fevers will go away once the illness causing it clears up. You can treat your fever with over the counter medication like Tylenol or Advil. See our section on Cold and Flu for tips on how to treat these conditions if this is what is causing your fever.
If your fever is from a bacterial infection, you may need to see a doctor or pharmacist for treatment.
Try to dress in light clothing when you have a fever, and keep the room temperature at 21°C (70°F) or lower to help you keep cool.
See a Doctor if Any of the Following Occur
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You are dehydrated and unable to keep water down. Signs that you may be dehydrated include feeling very thirsty and having dark, concentrated urine.
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Signs of a bacterial infections like pain, shortness of breath, urinating frequently or having blood in your urine.
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A change in your level of consciousness
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Your symptoms worsen or become more frequent.
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If your child is under 3 months or you are concerned for their wellbeing, you should see a doctor
Preventing Fevers
Fevers are a normal reaction to infection. The only way to prevent them is to prevent infection. Wash your hands frequently and wear a mask when you are in large groups during cold and flu season.
Having up to date immunizations can also protect you from illnesses that cause fevers.