Influenza A requires isolation. Influenza A is a contagious disease, mainly caused by viral infection, and its transmission is through respiratory droplet transmission. For influenza A patients once the diagnosis is clear, the need for early application of antiviral drugs. Most patients are significantly less contagious after antiviral treatment, which usually lasts about 5 days and is basically non-contagious after treatment. A small number of patients with influenza A may develop severe cases, and these patients need to be vigilant, the most common is severe pneumonia that can cause respiratory failure, for such patients need to be admitted to the intensive care unit, given a ventilator to assist respiration, this type of patients have the risk of death due to respiratory failure.