1. severe vomiting and difficulty in taking oral medication or absorbing in oral medication, 2. pregnant and nursing women, 3. subjects received lopinavir/ridonavir, ribavirin, monoclonal antibodies and other specific antiviral drugs in the week prior to admission, 4. subjects exist respiratory failure requiring mechanical ventilation, 5. subjects of shock, 6. subjects combined with other organ failure requires intensive care unit, 7. subjects with no clinical expectation of survival and only give end-of-life care, or those in a deep coma who did not respond to supportive treatment within three hours of admission.

1. severe vomiting and difficulty in taking oral medication or absorbing in oral medication, 2. pregnant and nursing women, 3. subjects received lopinavir/ridonavir, ribavirin, monoclonal antibodies and other specific antiviral drugs in the week prior to admission, 4. subjects exist respiratory failure requiring mechanical ventilation, 5. subjects of shock, 6. subjects combined with other organ failure requires intensive care unit, 7. subjects with no clinical expectation of survival and only give end-of-life care, or those in a deep coma who did not respond to supportive treatment within three hours of admission.