Hydrogen-Oxygen Generator With Nebulizer for Adjuvant Treatment of COVID-19 Positive Patients

Inclusion Criteria: * Male and female subjects aged between 18 and 80 years old (inclusive). * Diagnosed as general type of COVID-19 according to the criteria of Scheme for Diagnosis and Treatment of 2019 Novel Coronavirus Pneumonia (Trial Version 9). * Subjects who are willing to participate and provided written informed consent form. Exclusion Criteria: * Diagnosed as mild, severe, critical or asymptomatic type of COVID-19. * Subjects in the treatment or active stage of malignant tumor. * Subjects who are intolerable to inhalation treatment. * Subjects with mental disorders or cognitive impairment who are unable to provide consent. * Subjects with any immunodeficiency requiring chronic treatment with any corticosteroid or other immunosuppressants. * Complicate serious primary diseases such as heart, liver, kidney, and hematopoietic diseases; acute exacerbation phase of chronic obstructive pulmonary disease, or acute attack of bronchial asthma. * Subjects who are using any non-expectorant antioxidant drug, including large doses of vitamin C and vitamin E. * Subjects who are participating any other clinical study of any investigational drug or medical device. * Pregnant or lactating women. * Any other condition judged as inappropriate to participate in this study by the investigator.