The secondary end points included: 1) viral shedding duration, defined as the time from the illness onset to the first time the viral nucleic acid test was negative; 2) the severity of the disease,assessed by an area under the curve (AUC) analysis of a total of nine influenza-like symptom scores, the AUC was calculated as the product of the daily symptom scores times the duration of illness;3)frequency of Usage of Acetaminophen;4)and incidence of secondary complications of influenza, such as otitis, bronchitis, pneumonia，Nasosinusitis ,suppurative tonsillitis,acute parotitis，Reye'ssyndrome，central nervous system disease, Myocarditis and pericarditis, acute myositis, and toxic shock syndrome.5) economic evaluation.