Persistent fever

When the oral temperature is higher than 37.3 ℃ or the anal temperature is higher than 37.6 ℃, the day-to-day change exceeds 1.2 ℃, which is called fever. According to the level of fever, it can be divided into the following clinical divisions: low fever 37.4 ℃ ～ 38 ℃ moderate fever 38.1 ℃ ～ 39 ℃ high fever 39.1 ℃ ～ 41 ℃ super high fever 41 ℃ or more, lasting for more than 4 weeks, persistent fever .