Influenza A is very aggressive and its symptoms are more severe than those of the common cold, and the most severe time is usually on the 3rd-4th day after the onset of the disease, which varies from person to person. After the influenza A virus has invaded the body for 3-6 hours, the body temperature will rise sharply, accompanied by headache, general muscle pain, weakness and other symptoms. However, if immunocompromised patients do not receive effective treatment, complications such as pneumonia may arise, and the patient’s condition may become more and more serious at this time. Therefore, influenza A patients should take more bed rest, drink more hot water, and when high fever appears, it is recommended to visit the respiratory department of the hospital as early as possible to take symptomatic treatment to reduce heat treatment so as to avoid further aggravation of the condition and other complications.