We get fevers because our body's immune system raises the body's temperature set point in the brain (specifically in the hypothalamus) as a defense mechanism against infections and other illnesses. This increase in temperature makes the body's environment less hospitable to viruses and bacteria, helps the immune system work more efficiently, and stimulates various immune responses to fight off the infection. The hypothalamus acts like a thermostat, raising the body's temperature through heat production (like shivering) and heat retention to reach a new higher set point. Fevers are usually caused by infections, inflammation, medications, or immunizations and are generally part of the body's effort to fight illness rather than a disease themselves.
Why the Body Raises Temperature
- The hypothalamus increases the temperature set point due to signals from immune cells fighting infection.
- This triggers heat-generating processes like muscle shivering and reduces heat loss.
- The fever creates a less favorable environment for pathogens and enhances immune cell activity, such as helping white blood cells move more efficiently to infection sites.
Causes of Fever
- Most commonly caused by viral or bacterial infections like flu, COVID-19, or strep throat.
- Other causes include inflammation from chronic conditions, reactions to medications, vaccines, heat exhaustion, or certain cancers.
Role of Fever in Immunity
- Fever stimulates heat shock proteins that aid immune cells in fighting infections.
- It signals that the immune system is actively working to control the illness.
In summary, fever is a beneficial immune response designed to help the body combat infection more effectively.