Mechanism of fever:

Infections, toxins, immune complex, neoplasia————-> Leukocytes release cytokines including IL-1, IL-6, TNF, interferons.——–> They reach the brain and interact with vascular receptors in the thermoregulatory centre of hypothalamus.——————–> Production of prostaglandin then interacts with vascular centre in hypothalamus——-> This stimulates sympathetic nerves, decrease heat dissipation from the body and vasoconstriction occurs as a result of sympathetic stimulation————> All these action results in fever.

Functions of fever:

• Increased phagocytosis
• Increased production of neutrophils
• Distribution of leukocytes is accelerated due to decrease in viscosity of blood.
• Formation of antibodies occurs more quickly and in larger quantities.
• They possess bacteriostatic action.
• Antigen-antibody reactions occur more quickly.