Influenza A is usually not contagious when it is well. Influenza A virus can cause upper respiratory tract infection, inflammatory factors involved in the development of the disease, the blood system, respiratory tract, digestive tract, eyes and other parts of the inflammatory response leading to fever, secondary serious complications, etc.. The disease is highly contagious and occurs mostly in winter and spring. After being cured of influenza A, due to the production of specific antibodies in the body, the influenza virus in the body has been completely eliminated, belonging to the virus-free patients, and generally this group of people will not cause others to be infected with influenza. After influenza A is well, we should also pay attention to rest, do not stay up late; to balanced nutrition, drink more water, eat more fresh fruits and vegetables, appropriate exercise, enhance physical fitness, in order to improve immunity.