Why does our body generate a temperature above 36.8 C, up to 41.C wile been sick Are there some areas in the body experiencing higher temperatures and some lower ? But we are measuring just the averag. average
Circulating blood tends to produce a relatively uniform "average temperature." There are many (More than a dozen) processes that contribute to change of this average, but normally they produce an amazingly precise net effect despite much larger swings in the air temperature (solar heating, etc.). Illness interferes or modulates some of these processes - shifts the net equilibrium point. Perspiration (including moisture added to the exhaled air) and metabolic processes are among the most important of the dozen or so processes that settle to a common net equilibrium point. This point can not be maintained if the wet-bulb temperature is 35C (95F) or higher. I.e. your body will internally over heat and you will be dead in less than an hour, unless you can immerse part of your body in cooling water. A 75kg person, just sitting in a chair, watching TV etc. must dump approximately 100W to the environment, to avoid death. It is generally believed (me included) that mild fever is beneficial to curing most types of acute illness, but some means must be used to avoid brain damage for fevers or 104F or higher. NSAIDs, especially Aspirin, can cause ulcers, so a fore limb in cold water (ice if needed) is probably safer way to lower a temperature of 104F.
Let me site an example: arm Left is exposed to the sun . I imagine the skin surface of arm L might have a temperature of about 41 C, because the circulation of blood it will remove the heat that produce the high temperature and so the bulk of the arm L have 36.8 C. And so I think if we have some localized infection , the localized the temperature will be higher , but the total body might experience only some fraction increase of temperature . As you are pointing out that small increase might be beneficial to the total body . The benefit probable will be due to the rapid increase of the production of cells in the immune system.???
Vasodilation along with evaporation perspiration, yes. The bulk arm temperature may even rise ever so slightly if radiation is very strong. It is quite difficult for the body to produce sustained local increases in temperature. Fevers will generally apply to the core body temperature. Some interesting research indicates that fever enhances the heat shock response pathway. Heat shock proteins are also produced by cells after exposure to stressful conditions in most organisms. They augment host defences in the context of infection, inflammation and injury.
