Prior history of COVID-19,2)Positive test of total SARS-CoV-2 specific antibody using colloidal gold reagent[Only applicable to subjects without vaccination history of COVID-19 vaccine(marketedor investigational)],3)Pregnant or lactating women,4)Fever on the day of vaccination or within 3 days prior to vaccination (oral temperature =37.5°C/axillary temperature =37.3°C),5)Those who had any acute disease in the past 5 days that requires systemic antibiotic or antiviral treatment (including but not limited to the use of anti-influenza virus drugs such as Tamiflu, Relenza, Symmetrel or Flumadine),6)Those who had low immune function caused by immunodeficiency diseases, diseases of important organs,cancer, and immune diseases (e.g. Guillain Barre syndrome, systemic lupus erythematosus, rheumatoid arthritis, alienia or splenectomy caused by any condition, and other immune disease that may affect immune response at the investigator’s discretion),7)Long-term use (defined as =14 days) of immunosuppressants or other immunomodulators (for glucocorticoids, e.g., =10 mg/day prednisone or equivalent dose, inhaled and topical steroids are allowed) within 6 months prior to the first vaccination,8)History of hemorrhagic diseases (e.g., factor deficiency, thrombocytopenia or other coagulation disorders), or hemorrhagic tendency, or continuous requirement of anticoagulants,9)Having received immunoglobulins and/or blood products within 3 months before receiving the investigational vaccine,10)Received subunit or inactivated vaccine within 14 days before vaccination, or received live attenuated vaccine within 28 days before vaccination,11)Participation in a clinical trial of another product within 1 month prior to vaccination, or planning to participate in a clinical trial of another product during the study, A phase III clinical trial of influenza virus vector COVID-19 vaccine for intranasal spray (DelNS1-2019-nCoV-RBD-OPT1) Protocol No.: COVID-19-PRO-003Version No/Date: 2.0/ August 10, 2021Confidential3612)Having a history of severe allergic reactions or severe adverse reactions from previous immunizations, or allergy to any component of the investigational vaccine,13)Patients deemed by the investigator as unsuitable for using nasal spray (those with severe rhinitis or nasal deformities, etc.),14)Planning to relocate permanently from the current area prior to the completion of the study or to leave the current area for a long period (preventing compliance with the prescribed visit schedule) during the study visits,15)Other conditions that the investigators consider unsuitable for this clinical study.

Prior history of COVID-19,2)Positive test of total SARS-CoV-2 specific antibody using colloidal gold reagent[Only applicable to subjects without vaccination history of COVID-19 vaccine(marketedor investigational)],3)Pregnant or lactating women,4)Fever on the day of vaccination or within 3 days prior to vaccination (oral temperature =37.5°C/axillary temperature =37.3°C),5)Those who had any acute disease in the past 5 days that requires systemic antibiotic or antiviral treatment (including but not limited to the use of anti-influenza virus drugs such as Tamiflu, Relenza, Symmetrel or Flumadine),6)Those who had low immune function caused by immunodeficiency diseases, diseases of important organs,cancer, and immune diseases (e.g. Guillain Barre syndrome, systemic lupus erythematosus, rheumatoid arthritis, alienia or splenectomy caused by any condition, and other immune disease that may affect immune response at the investigator’s discretion),7)Long-term use (defined as =14 days) of immunosuppressants or other immunomodulators (for glucocorticoids, e.g., =10 mg/day prednisone or equivalent dose, inhaled and topical steroids are allowed) within 6 months prior to the first vaccination,8)History of hemorrhagic diseases (e.g., factor deficiency, thrombocytopenia or other coagulation disorders), or hemorrhagic tendency, or continuous requirement of anticoagulants,9)Having received immunoglobulins and/or blood products within 3 months before receiving the investigational vaccine,10)Received subunit or inactivated vaccine within 14 days before vaccination, or received live attenuated vaccine within 28 days before vaccination,11)Participation in a clinical trial of another product within 1 month prior to vaccination, or planning to participate in a clinical trial of another product during the study, A phase III clinical trial of influenza virus vector COVID-19 vaccine for intranasal spray (DelNS1-2019-nCoV-RBD-OPT1) Protocol No.: COVID-19-PRO-003Version No/Date: 2.0/ August 10, 2021Confidential3612)Having a history of severe allergic reactions or severe adverse reactions from previous immunizations, or allergy to any component of the investigational vaccine,13)Patients deemed by the investigator as unsuitable for using nasal spray (those with severe rhinitis or nasal deformities, etc.),14)Planning to relocate permanently from the current area prior to the completion of the study or to leave the current area for a long period (preventing compliance with the prescribed visit schedule) during the study visits,15)Other conditions that the investigators consider unsuitable for this clinical study.