Yes, the fever can occur due to multiple reasons but since you are asking particularly about fever that occurs in an infection due to fight between pathogen(releases toxins) and WBC(releases interleukin-1). These toxins and interleukin are also called pyrogen. These pyrogens act on hypothalamus and increase temperature. This increase in temperature is actually very important and we shouldn't use meds to supress this(low-grade fever) because as you know that pathogens are made of proteins and enzymes which are heat labile and do not function well(gets denatures) in high temperature. Fever in such case is an immune response produced by body to fight pathogens.
But if the temperature is very high then one should take meds as the metabolic costs(our body is also made of proteins and enzymes which also get denatured because of rise in temperature, this is why we don't feel hunger in fever.) is much higher than the potential physiological benefit. One also take anti pyretics to avoid the symptoms of fever like headache, muscle ache etc.
You should also remember that these anti pyretics only help with the symptoms of fever and not the actual cause of disease.
I hope this helped.
Thank you!
