Classification by degree of fever
Based on axillary temperature: low fever: 37.5~38°C. Moderate fever: 38.1~38.9℃. High fever: 39~41°C. Super high fever: over 41°C.
Classification by duration of fever: Short-term fever: refers to fever <2 weeks, mostly accompanied by local symptoms and signs. Long-term fever: refers to fever ≥ 2 weeks, some may have no other obvious signs and symptoms, and requires laboratory tests for diagnosis. Fever awaiting investigation: fever lasting for more than 2 weeks, with a body temperature of 37.5°C or more, and the diagnosis cannot be confirmed by physical examination and routine laboratory tests. Chronic hypothermia: is defined as a low fever lasting for more than 1 month.
According to the classification of fever’s heat type, the common heat types of fever are usually classified into 6 types.
Dyscalculia: A fever in which the body temperature remains constant at 39.0-40.0°C for several days or weeks, with temperature fluctuations of no more than 1.0°C over a 24-hour period.
Flaccid fever: The body temperature is often above 39.0°C and fluctuates widely, with a range of more than 2.0°C within 24 hours, but is above normal.
Intermittent fever: A sudden rise in body temperature that peaks for a few hours and then drops rapidly to a normal level, with periods of no fever (intermittent periods) lasting from one to several days.
Fluctuating fever: A gradual rise in body temperature to 39.0°C or more, lasting for several days, followed by a gradual fall to a normal level, followed by a gradual rise for several days, and so on.
Regressive fever: a sharp rise in body temperature to 39.0°C or above, lasting several days and then dropping abruptly to a normal level, with periods of high fever and periods of no fever each lasting several days and then alternating regularly once.
Irregular fever: the temperature profile of fever is not necessarily regular.