The cycle of infectious fever - how it affects bacterial infections

Fever is one of the human body's most effective strategies in fighting infections. However, its precise role in eliminating pathogens, specifically the influence of heat on the bacterial cells on the mechanistic level under febrile temperatures has never been fully delineated. The concept of fever, as the immune system's first line of defense against pathogens involves two main components: the inflammatory response and the heat, which stimulates the host's immune cells and affects pathogens. This article summarizes independent findings, grouping the development of fever into a circular model, starting with pathogen invasion and the release of bacteria's exogenous pyrogens, continuing through the host immune response, and debating on the impact of fever on numerous human pathogens. This model focuses broadly on processes occurring within bacteria, particularly pathogen adaptation and the detrimental effect of heat released during fever on pathogen death. We also discussed the impact of commonly used antipyretics, such as acetaminophen, ibuprofen, and aspirin, on the overall outcome of infection and provided a framework within which new concepts and findings in this field can be developed.