What is Fever?



Fever is a most common symptom of illness. Fever is an increase in body temperature over 37.5 degree Celsius.  Fever alone is not a disease. But it is a symptom of many diseases.
It is known that the body temperature varies throughout the day, but the body does not need to warm up or cool down. Our behavior, however, adjusts itself to clothing or hot or cold, depending on the temperature.

The body fever is controlled by the hypothalamus, which is located in the central nervous system.
There are three types of nerves found in the hypothalamus.

1. Heat-sensitives:-  heat sensitive pre optic neurons 20% of these temperatures increase their activity when the head temperature is adjusted.
2. 10% cold sensitive:- These are stimulated by cold wether.
3. 70% temperature insensitive parts of the hypothalamus:-  are neither sensitive to heat nor to cold.

Where are common areas body temperature measured?
1. oral
2. rectal
3. otic/ear drum
4. axillary/arm pit
5. temporal artery

By the way, body temperature varies depending on where you measure it. In our country it is said that we can measure the anus of the pediatrics and  adult's oral temperature. Another good option is to measure it from the forehead or ear.

What are the causes of fever?
1. Infection with microorganisms
2. Auto immune illnesses
3. Iatrogenic or drug induced
4. Cancer 

Dr. Beza

References:
2. Medscape, Are we wrong about Fevers, https://www.medscape.com/viewarticle/903555