A fever is an increase in body temperature above the normal temperature, usually caused by an infection. Normal body temperature is around 37°C, although there may be some minor fluctuations over the course of the day and night.
Infection is usually the cause of fevers in the general public. These often include the common cold, tonsillitis, pneumonia [infection of the lungs] and gastroenteritis [a tummy bug that causes diarrhoea and vomiting].
More rarely, long-term illnesses such as rheumatoid arthritis, heat stroke and at times, some cancers, can cause a fever.
Why do I get a fever?
A fever triggered by a viral or bacterial infection is caused by chemicals produced by the immune system. Most cases of mild fever clear up by themselves within a couple of days. A mild fever [up to 39°C] can actually help the immune system to get rid of an infection.
Contrary to popular belief, the severity of fever isn’t necessarily related to the seriousness of the illness – for example, life-threatening meningitis [an infection of the protective layers surrounding the brain] may only cause a small rise in temperature.
What are the symptoms of a fever?
The symptoms of fever include:
- Feeling generally unwell
- Feeling hot and sweaty
- Shivering
- Chattering teeth
- Flushed face
In children between the ages of 6 months and 6 years, fever can occasionally trigger convulsions. A fever of 42.4°C or higher can sometimes permanently damage the brain, particularly in the elderly.
My child has a fever. What should I do?
Fever is common in children. On average, a child has up to 10 infections per year.
However, body temperature isn’t actually a reliable indicator of illness for babies and young children – a child may have a mild rise in temperature according to the thermometer [slightly over 37°C], and still seem happy and healthy.
Dr Kannan always advises to seek medical help if your child has a temperature and:
- Is aged 6 months or younger
- Has a rash
- Has a fever of 40°C or more
- Still has a fever after a day or two, even after taking baby/child paracetamol
- Vomits or has persistent diarrhoea
- Refuses food or drinks
- Cries inconsolably
- Appears floppy, non-responsive or just looks unwell to you
- Starts having convulsions or twitches
- Has trouble breathing
- Is in pain
- If you feel worried or concerned at any stage
I have a mild fever. Can I treat it at home?
You can treat a mild fever yourself by taking the appropriate doses of paracetamol [provided you’re not allergic] to help bring your temperature down, as well as:
- Drinking plenty of plain water
- Avoiding alcohol, tea and coffee as these drinks can cause slight dehydration
- Sponging exposed skin with tepid water
However, you should always consult a doctor if:
- You are still feverish after 3 days, despite home remedies
- Your temperature is over 40°C
- You are shivering and shaking involuntarily, or your teeth are chattering
- You feel hot but are not sweating
- You feel more unwell as times goes by
- You have unusual symptoms, such as vomiting, neck stiffness, skin rash, rapid heart rate, chills or muscle spasms
- You feel confused and drowsy
- You have a severe headache that doesn’t respond to painkillers
- You have recently travelled overseas
You should always see your doctor immediately if you have a fever with a headache, stiff neck or a rash that does not disappear when you apply pressure, as this indicates bleeding in the skin. This can at times indicate a life-threatening illness.
How will the doctor treat my fever?
This depends on why you have a fever. For example, if you have chronic tonsillitis, you may need surgery to have your tonsils removed [tonsillectomy].
If your fever is caused by a viral infection, don’t bother asking your doctor for antibiotics, as they won’t have an effect on the virus. And in cases of mild bacterial infection, it is usually best to rest well and let your immune system handle the problem. Your doctor will be able to suggest the best course of action for you!
Everything was great until the tingly sensation arrived. With alternating feelings of being equator-level toasty and ice-cream-aisle freezing, you soon found yourself asking the question to end all questions, “Do I feel warm to you?” Historically, having a temperature above, or below, 98.6° Fahrenheit might have been alarming. But we are here to break some fever madness: Body temperatures exist on a spectrum.
The History of Body Temperature
Today’s standard body temperature was coined by Carl Reinhold August Wunderlich in 1868. A German physician, Wunderlich sampled over 25,000 individuals’ armpits to find the now-commonplace average body temperature of 98.6° Fahrenheit—we’re going to go out on a limb and say that the standard body temperature of 25,000 people in 1868 is no longer true in today’s standards.
“This temperature standard is widely used in both the clinical and home setting. But now, we are challenging its credibility,” said Evelyn Balogun, M.D., medical director of Inspira Urgent Care, Occupational Health and Employee Health. “Researchers found that body temperature changes throughout the day and varies person to person. For example, Harvard Health reported that women have higher body temperatures than men, younger people have higher temperatures than those of advanced age, and most notably, average body temperatures are decreasing, some dipping as low as 97.5° Fahrenheit.”
The Fever Backstory
While the standard body temperature may exist on a range, one thing has remained constant: the definition of a fever. According to the Centers for Disease Control and Prevention [CDC], a fever is defined as having a measured temperature of 100.4° F, being warm to the touch or feeling feverish.
“Fevers are caused by your body trying to attack unwelcome germs, viruses or bacteria,” said Dr. Balogun. “Think about it like this: Sometimes your body can kill infections at your normal body temperature. But sometimes, there are infections that need to be killed at a high temperature. So, your body pre-heats your immune system and bakes the bacteria away. When it’s all cooked, it turns the oven off and your body cools down.”
The Right Way to Take Your Temperature
Every illness requires unique treatment, so diagnosing and treating your fever is no different. “Taking your temperature and getting an accurate read depends on your testing method, environment and recent activities,” said Dr. Balogun. “The best way to take your temperature is with an oral thermometer. The CDC recommends waiting 30 minutes after eating, drinking or exercising to take your temperature. Additionally, you should wait a minimum of six hours after taking fever-reducing medication [like acetaminophen] before taking your temperature to get an accurate reading.”
The Difference Between a Fever and a COVID-19 Fever
Fluctuating body temperatures are a normal part of the human body; however, there is a difference between a warmer body temperature at certain parts of the day and having a consistent fever. “By the end of the day, after you’re done running your errands, going to work and cooking dinner, you’re going to be warmer than you were in the morning after you just woke up. There’s a big difference between this and a ‘fever warm’—which is accompanied by fatigue, headaches and even chills,” said Dr. Balogun. “And in the midst of COVID-19, understanding your body and its response to illness is more important than ever.”
Having a fever is one of the COVID-19 symptoms, but it is not the only one. The characteristic symptoms of the coronavirus include, but are not limited to: sore throat, loss of taste and smell, body aches and shortness of breath.