When a baby has a low fever, the first thing to determine is whether the fever is caused by a disease. When a fever is considered to be due to an infection, other than a transient high body temperature caused by ambient temperature, violent crying, or activity, whether or not the low fever can heal itself depends on the original disease. If it is a common viral infection, it can heal on its own, and the course of treatment is about 3-7 days, usually the fever is more obvious in the first 3 days. If there is a bacterial infection or mycoplasma infection, when the infection is more obvious and serious, it is usually not easy to heal itself in a short period of time, and it is necessary to do laboratory tests such as routine blood tests and mycoplasma, as well as other symptoms that may be associated with the baby, to diagnose the original disease and treat it as appropriate. For febrile diseases, attention needs to be paid to drinking warm water appropriately and regularly to ensure fluid intake, which is conducive to the recovery of normal body temperature.