About Fever

Fever is a normal body reaction when there is an infection or other illness. In most cases, a fever is a healthy reaction of the body's immune system to help fight viruses. However, it is  crucial to understand the different types of fevers and when to seek medical advice. This article will explore the definition of fever, different types of fever and when to seek medical advice and ways to self-manage a fever. 


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What is fever?
What is fever?

Definition of Fever

Fever is when the body temperature exceeds the normal range by 0.58℃/ 1℉ or more. The normal body temperature is usually between 36.5℃ to 37.5℃. So under normal circumstances, when the body temperature exceeds 38℃/100.4℉, we call it a fever; when the body temperature exceeds 39.5℃/103.4℉, we call it a high-grade fever or even Hyperpyrexia.


Fever is usually a reaction of the body under infection, inflammation, or other diseases. The immune system releases pyrogens when our body detects pathogens such as bacteria or viruses,. It helps to improve the immune system’s effectiveness  and suppress the pathogens’ growth.

Different kinds of fever
Different kinds of fever

Fever can be classified into different types, including:

  • Continuous fever: The body temperature hovers around 39-40°C, with very low-temperature fluctuations between day and night.
  • Remittent fever: The continuous fluctuation of body temperature is more significant than that of remittent fever,  the body temperature may rise and fall throughout the day, with the fluctuations typically exceeding 1 degree Celsius (1.8 degrees Fahrenheit).
  • Intermittent fever: The body temperature will suddenly rise above 39°C and return to normal after a few hours. After a few hours or a day or two, the body temperature will rise again, and the cycle recur.
  • Relapsing fever: Though similar to intermittent fever, the high-grade fever can last several days and then drop to normal. After a certain period, the fever returned. After a few days, the body temperature will drop to normal.
The causes of fever
The causes of fever

The causes of fever can also be ascribed into the following types: 

  • Viral fever: Viral infections are one of the most common causes of fever. For example, colds, flu, and dengue fever are fevers caused by viruses. This type of fever often brings with other symptoms, such as sore throat, cough (phlegm may appear thick and yellowish), headache and muscle pain.
  • Bacterial fever: Bacterial infections are also common causes of fever. For example, strep throat can cause tonsillitis and have symptoms such as high-grade fever, sore throat, and cough (without thick phlegm). Other bacterial infections, such as urinary tract infections and pneumonia, may also cause fever.
  • Parasitic infections: Certain parasitic infections, such as malaria, may also cause fever. These infections are often associated with bites from mosquitoes or other insects.
  • Medication-induced fever: Certain kinds of medication may cause allergic reactions or other adverse reactions that lead to fever.
  • Other causes: Other causes of feverinclude immune system diseases, tumors and endocrine disorders.


The misconception that fever causes growth spurts: In reality, there is no direct relationship between a child’s growth and having a fever. Some theories suggest that children may be more susceptible to illness during periods of rapid growth when their immune system is relatively weaker. This misunderstanding leads many people to believe that fever can contribute to growth spurts.

Do I need to see a doctor?
Do I need to see a doctor?

Although fever is a normal reaction of the body in most cases, in some cases, it is necessary to seek medical advice. You should seek help from a medical professional if you have:

  • Persistent high fever: Medical advice should be sought if a fever lasts more than three days and the temperature exceeds 38.5°C. A persistently high-grade fever may be a sign of serious infection or other illness.
  • Severe symptoms: If fever is accompanied by severe symptoms, such as severe headache, difficulty breathing, chest pain, confusion, or persistent vomiting, you should see a doctor immediately.
  • Young children: In young children, especially infants under three months of age, even a low-grade fever may require medical advice. A paediatrician can evaluate the cause of the fever and provide appropriate treatment.
  • Immune system problems: If you have an immune system problem, such as if you have had an organ transplant, are undergoing chemotherapy, or have HIV/AIDS, a lower fever may also require you to seek medical advice.
  • Other symptoms: If your fever is accompanied by other symptoms, such as severe abdominal pain, rash, joint pain, or blood in the urine, you should seek medical help immediately.
Ways to self-manage a fever
Ways to self-manage a fever

Before seeking medical advice, you can take the following self-care measures to manage your fever:

  • Rest and stay hydrated: Resiting helps the body to recover and fight off the infection. Also, ensure adequate liquid intake to avoid dehydration.
  • Maintain a comfortable room temperature: Keeping the room temperature cool and well-ventilated. Wearing lightweight clothing can help lower body temperature.
  • Take fever-reducing medications: You can use over-the-counter fever-reducing medications, such as ibuprofen or acetaminophen, to relieve fever and discomfort. However, before using any medication, read and follow the instructions, or consult with your doctor or pharmacist for advice..
  • Monitor symptom changesm: Keep an eye on any changes, such as the duration of the fever, severity of other symptoms, and if there is any other associated symptoms that appears.

Fever is the body's normal reaction to an infection or other illness.Still it's important to understand the different types of fever and when to seek medical advice. In most cases, lower-grade fevers can be managed with self-care measures, but in some cases, seeking medical advice and treatment from doctor is necessary. Remember, if you have any questions or concerns, always ask your family doctor for help.


When you have a fever, is it helpful to take a shower with HOT water?

The correct answer is to take a shower or bath in lukewarm water, not hot water, and certainly not a cold bath.  This is because cold water will only cause the pores and capillaries on the patient's skin surface to rapidly contract, which is not conducive to the body's core temperature dissipation.


What should I do if my high-grade fever persists?

As mentioned above, fever is a reaction of the body when there is infection or other illness. If a high fever persists, it may be a sign of serious infection or other illness. you should seek medical advice immediately to find out the cause.


Is it helpful to sweat all over when you have a fever?

Having too many clothes/quilts will increase body temperature, and sweating too much can also lead to dehydration, which is not efficient for cooling down body temperature. We would recommend wearing lightweight clothing, which is more conducive to the body's natural heat dissipation. As fever itself is not a disease, but a symptom. We should focus on finding out the cause of the fever and prescribing the right medication.

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