There are several reasons why low fever does not subside all the time: 1. It may be due to recurrent viral infections, often seen in patients with colds, who often get viral infections due to low immunity, so the low fever recurs and does not improve after a long period of treatment. 2. The presence of chronic diseases that lead to recurrent low fever, such as tuberculosis or diseases of the blood system, and tumor-like diseases, such as The most common clinical conditions are leukemia, lung cancer, gastric cancer, and other related tumor diseases. 3. For recurrent low fever, there is also a condition that is medically unidentifiable, that is, unexplained recurrent low fever. Although the cause cannot be identified, we should actively treat the symptoms, choose appropriate antipyretic drugs, and continue detailed examination to eventually find the cause and resolve the low fever.