1) The confirmed patient (or legal guardian) agrees to participate in the study and signs the informed consent form, 2) aged 18 to 65 years, 3) Real-time fluorescent RT-PCR of respiratory specimens or blood specimens to detect patients with new type of coronavirus positive, 4) Patients diagnosed as severe and critically ill and with rapid disease progression according to the Diagnosis and Treatment Program for Pneumonia of New Coronavirus Infection (Trial Version 6) .

1) The confirmed patient (or legal guardian) agrees to participate in the study and signs the informed consent form, 2) aged 18 to 65 years, 3) Real-time fluorescent RT-PCR of respiratory specimens or blood specimens to detect patients with new type of coronavirus positive, 4) Patients diagnosed as severe and critically ill and with rapid disease progression according to the Diagnosis and Treatment Program for Pneumonia of New Coronavirus Infection (Trial Version 6) .