Influenza, also known as the flu, is primarily due to an infection of the flu virus in our upper respiratory tract, leading to symptoms such as sore throat, cough, and fever. After the influenza virus enters the human body, it replicates repeatedly. Post replication, the body's immune cells attempt to eliminate it. However, it is usually challenging for immune cells to completely clear the virus in one go. Therefore, many patients experience a prolonged period of low-grade fever or persistent abnormal body temperature after the flu. Generally, the course of the flu is about 10-14 days, and recovery is typically achievable, often with a complete resolution of fever. Thus, there is no need for excessive worry. Treatment can be effectively enhanced by using a combination of antiviral Chinese and Western medicines.