Adults with a body temperature of 39℃ or above, burning overnight has a greater impact on the body and may cause generalized aches and pains, headaches and other symptoms, which should be actively treated at a fever clinic or internal medicine department. In clinical practice, body temperature between 37.3℃-38℃ is low fever, 38.1-39℃ is moderate fever, 39.1-41℃ is high fever, and over 41℃ is super high fever. 39℃ mostly belongs to high fever status, which needs medical treatment without delay. In adults, after a night, if the body temperature does not drop, it means that there is a more serious inflammatory reaction, even if the body is better, it will become weaker, with headache, general muscle aches, dizziness, weakness, nausea, vomiting and other symptoms. It is necessary to improve the relevant examination, clarify the cause of fever and follow the medical advice for treatment so as not to delay the condition. When you have a fever, you should pay attention to rest, drink more water, and eat nutritious food in moderation, especially vitamin-rich fruits and vegetables, to improve the body’s ability to resist disease.