Fevers - An Immune Response to Look Out for!

Why do people have fevers when they feel unwell? Sometimes, it seems expected as a symptom of a disease. Other times, they may become alarming, especially when internal temperatures exceed 38°C.

Some instances when individuals experience fever may include: viral or bacterial infections such as common colds and skin infections, and autoimmune or inflammatory diseases such as arthritis and ulcerative colitis (inflammation in the digestive tract).

According to Penn Medicine, fever is defined as the increase in body temperature in response to a disease (it is a somatic/physical symptom). Most pathogens can survive at 37°C, so the body fights against this by increasing its temperature. Thus, the enzymes that sustain the biological processes within these pathogens will not function, impairing its replication, and facilitating cell death.

When an individual is infected, a virus or harmful bacteria (pathogen) has entered the body by passing through the first and second line of defense. The first line of defense includes impermeable barriers that prevent entry of harmful microorganisms. For example, the skin, nose and throat mucous, and stomach acid. They prevent the proliferation of pathogens inside the body, by blocking their entry.

Additionally, when pathogens pass through the first line of defense, they enter the second line of defense, which consists of phagocytes (a type of white blood cell) that provide nonspecific resistance. Nonspecific resistance is the process of removing pathogens and foreign substances detected by the body, without considering their characteristics, and producing memory cells for a secondary immune response through the third line of defense. The third line of defense will not be covered here, but it is made of lymphocytes (yes, another type of white blood cell) that produces highly specific antibodies to handle stubborn pathogens. Back to the second line of defense - the phagocytes actively engulf and digest the pathogens, eventually eliminating their population, considering its controlled spread.

At the same time, the second line of defense responds with inflammation and fever. When the skin barrier is damaged, internal tissues become exposed to pathogens which may result in an infection. The immune cells become activated in that specific area. These specific cells secrete substances that cause the blood vessels surrounding the wound to be enlarged (dilated). This is done to increase blood flow, which brings with it white blood cells to fight off the infection. However, externally, the area turns red and swells. This response would be followed by an increase in body temperature.

In children and adults, a body temperature of or above 37.2°C to 38°C indicates a fever. However, beyond this range, immediate medical attention should be considered. An important consideration would be infants. They often have high fever alongside illnesses and infections. Handling fever in infants requires consistent monitoring. Although, usually fevers will not exceed 40.6°C during an infection. Moreover, brain impairment would not usually occur, unless it reaches beyond 42°C in infants.

Our bodies are really strong, so let’s support it through proper care and treatment (even at home). Please note that the suggestions below are to increase immune health and reduce discomfort of illness. They may be applied to those with mild to high fevers.

Wear breathable clothing, and use a lightweight blanket. The individual should not be too hot or too cold.

Stay hydrated (drink lots of fluids, such as water, electrolytes drink, and soups).

Eat warm and softer foods.

Some medicine that may be helpful for treatment include ibuprofen (e.g. Neurofen, Tylenol), and paracetamol (e.g. Panadol).

*ibuprofen and paracetamol are the chemicals, while Neurofen, Tylenol, and Panadol are medicine brands recommended.

Finally, an individual should be well if they are alert, interested in other activities, and eating and drinking well. If the fever persists for more than a week, and continues with abnormal symptoms even after home treatment and rest, please seek professional medical attention immediately.

Have a restful day!

References

Fever - Symptoms and Causes. (n.d.). Www.pennmedicine.org. Retrieved January 24, 2024, from https://www.pennmedicine.org/for-patients-and-visitors/patient-information/conditions-treated-a-to-z/fever#:~:text=Fever%20is%20the%20temporary%20increase

Institute for Quality and Efficiency in Health Care. (2020, July 30). The innate and adaptive immune systems. Nih.gov; Institute for Quality and Efficiency in Health Care (IQWiG). https://www.ncbi.nlm.nih.gov/books/NBK279396/

Mayo Clinic. (2017). Fever - Diagnosis and treatment - Mayo Clinic. Mayoclinic.org. https://www.mayoclinic.org/diseases-conditions/fever/diagnosis-treatment/drc-20352764

Wrotek, S. (2020). Let fever do its job. Evolution, Medicine, and Public Health, 9(1). https://doi.org/10.1093/emph/eoaa044