A weak positive test for influenza virus indicates the occurrence of influenza virus infection. Whether the condition is serious or not needs to be judged in the light of the patient’s clinical symptoms. A weak positive test for influenza virus antibody, antigen or nucleic acid indicates that influenza virus infection has occurred. Most patients are not in serious condition, with mild or moderate fever, mild systemic and respiratory symptoms, and can recover or recover within 2-3 days. Some patients may develop epidemic viral pneumonia, which may include high fever, dyspnea, wheezing, shortness of breath, coughing, chest pain, and even respiratory failure, which is a relatively serious condition that requires hospitalization and active treatment as soon as possible. In addition, some patients may also develop viral encephalitis, viral myocarditis, infectious shock and other very serious complications, which are even more serious and require early detection and early treatment.