Immune Response to Fevers

immune response: reaction of the body to foreign matter

What is a fever?

A fever is a natural body defense against infection. The normal body temperature for a human is 98.6 degrees Fahrenheit. Anything above 99 degrees Fahrenheit is considered a fever. A fever occurs when the part of your brain called the hypothalamus recognizes a virus and moves your normal body temperature higher. This happens when your body is trying to kill a virus.

Fevers are a 2nd line of defense in the immune system which is an inflammatory response. This is an increased white blood cell production, blood vessel expansion, and infected tissue becomes swollen or painful and a fever occurs. The heat of a fever kills pathogens. Pathogens are organisms that cause disease. Pathogens are a bacterial infection in fevers. They recognize foreign things such as bacteria and virus. Fevers are the immune system's way of fighting off infection. The immune system makes antibodies during infection. Antibodies are proteins made in response to antigens. Antigens cause pathogens to clump together.
During a fever a person's blood and urine volume is lowered due to loss of water through increased perspiration. Your body will be protected from invasion by the same pathogen because the heat of a fever kills off the pathogens.