Influenza A is a very common upper respiratory tract infection caused by the H1N1 influenza virus after infecting the respiratory tract. Typically, patients with this type of flu will experience varying degrees of fever, and the body temperature tends to be quite high during fevers. Commonly, these patients may experience headache, dizziness, reduced appetite, and general weakness during the acute phase of infection. For patients with influenza A, due to the high fever, some may experience gastrointestinal discomfort, including nausea and vomiting. This is mainly because the fever can affect normal digestive functions. Thus, when these patients eat slightly more than usual, they may experience gastrointestinal discomfort. Therefore, it is common for these patients to experience varying degrees of nausea and vomiting, particularly in conjunction with headaches or when they have sore throats and coughs. As long as timely antiviral and symptomatic supportive therapies are administered, once the influenza A virus is effectively controlled, the symptoms of vomiting will also be alleviated.