Influenza A is a common acute respiratory infection caused by the influenza A virus. It has a high incidence and mortality rate in children. Once a child has influenza A, he or she should be taken seriously and treated aggressively. Influenza A is an acute infectious disease, the source of infection is mainly patients with influenza A and patients with latent infection, its incubation period is short, only a few hours to 4 days, usually 1 to 3 days. Typical influenza A has a rapid onset, with mild respiratory cata symptoms and significant systemic toxicity. Newborns with influenza may have a sudden onset of high fever or a temperature that does not rise, do not eat milk, are irritable and weak, and other sepsis-like manifestations, which may be accompanied by a stuffy and runny nose. Influenza in young children can occur as upper respiratory tract infection, bronchitis, capillary bronchitis and pneumonia, often accompanied by high fever, moderate toxic symptoms and runny nose. School-age children and adolescents with influenza are similar to adults in that they have a sudden, high fever with a temperature of 39 to 41 degrees Celsius, flushed cheeks, congested conjunctiva, generalized symptoms such as muscle pain, headache, fatigue, poor appetite, and respiratory symptoms such as nasal congestion, runny nose, and dry cough. 1/3 of patients have diarrhea with watery stools. As mentioned above, if a child has influenza A, it is still serious. Once influenza A is clear, anti-influenza medication, such as oseltamivir phosphate pellets, should be given promptly, and heat treatment should be done promptly, along with isolation measures to prevent transmission to others. Annual influenza virus vaccination is recommended to prevent influenza.