A bout of chills is usually referred to clinically as a chill, and is seen in fevers of various causes. The body feels a chill as a result of the thermogenic source acting on the thermoregulatory center’s thermostat, causing it to be upregulated. At this time, the thermoregulatory center to re-regulate the body temperature, through the metabolic increase or make the skeletal muscle paroxysm, i.e., chills, so that the heat production increases. It can also make the skin blood vessels and vertical hair muscle contraction, stop sweating, and reduce heat dissipation. Clinical fever mainly includes infectious fever and non-infectious fever. 1. Infectious fever: the pathogens that cause infectious fever are bacteria, viruses, mycoplasma, rickettsiae, spirochetes, fungi and parasites. Various pathogens invade the human body can cause corresponding diseases, whether acute or chronic, focal or systemic can cause fever. 2. Non-infectious fever: Fever caused by causes other than pathogens is called non-infectious fever. It mainly includes absorption fever caused by tissue necrosis, decomposition and absorption; fever caused by activation of pyrogenic cells by antigen-antibody complexes produced by metabolic reactions; and central fever caused by direct damage to the thermoregulatory center, which shifts the thermoregulatory point upward and sends out regulatory impulses. A bout of chills that persists without relief suggests prompt medical attention.