1. have a history of seizures, epilepsy, encephalopathy, psychosis. 2. history of severe anaphylaxis or allergy to any vaccine component. 3. positive urine pregnancy test result, pregnant, lactating women. 4. medical history of guillain-barré syndrome. 5. have had asthma attacks within 2 years. 6. have severe nasal or oral diseases, such as rhinitis (sinusitis), allergic rhinitis, oral ulcer, throat swelling, etc. 7. bleeding disorder (e.g. protein s or factor deficiency, coagulopathy or platelet disorder). 8. have chronic systematic infection or chronic obstructive pulmonary disease (copd), etc. 9. administration of immunoglobulins and/or any blood products within three months prior to the planned administration of the vaccine candidate. 10. current diagnosis or receiving treatment for tuberculosis or cancer. 11. history of sars-cov-2 infection for less than 3 months. 12. received or plan to receive any vaccines (licensed or investigational), within 14 days before and after study vaccination. 13. have an axillary temperature of \> 37.0℃. 14. any other significant diseases, disorders or findings which may significantly increase the risk to the volunteer because of participation in the study, and affect the ability of the volunteer to participate in the study or impair interpretation of the study data.

1. have a history of seizures, epilepsy, encephalopathy, psychosis. 2. history of severe anaphylaxis or allergy to any vaccine component. 3. positive urine pregnancy test result, pregnant, lactating women. 4. medical history of guillain-barré syndrome. 5. have had asthma attacks within 2 years. 6. have severe nasal or oral diseases, such as rhinitis (sinusitis), allergic rhinitis, oral ulcer, throat swelling, etc. 7. bleeding disorder (e.g. protein s or factor deficiency, coagulopathy or platelet disorder). 8. have chronic systematic infection or chronic obstructive pulmonary disease (copd), etc. 9. administration of immunoglobulins and/or any blood products within three months prior to the planned administration of the vaccine candidate. 10. current diagnosis or receiving treatment for tuberculosis or cancer. 11. history of sars-cov-2 infection for less than 3 months. 12. received or plan to receive any vaccines (licensed or investigational), within 14 days before and after study vaccination. 13. have an axillary temperature of \> 37.0℃. 14. any other significant diseases, disorders or findings which may significantly increase the risk to the volunteer because of participation in the study, and affect the ability of the volunteer to participate in the study or impair interpretation of the study data.

have a history of seizures, epilepsy, encephalopathy, psychosis. history of severe anaphylaxis or allergy to any vaccine component. positive urine pregnancy test result, pregnant, lactating women. medical history of guillain-barré syndrome. have had asthma attacks within 2 years. have severe nasal or oral diseases, such as rhinitis (sinusitis), allergic rhinitis, oral ulcer, throat swelling, etc. bleeding disorder (e.g. protein s or factor deficiency, coagulopathy or platelet disorder). have chronic systematic infection or chronic obstructive pulmonary disease (copd), etc. administration of immunoglobulins and/or any blood products within three months prior to the planned administration of the vaccine candidate. current diagnosis or receiving treatment for tuberculosis or cancer. history of sars-cov-2 infection for less than 3 months. received or plan to receive any vaccines (licensed or investigational), within 14 days before and after study vaccination. have an axillary temperature of > 37.0℃. any other significant diseases, disorders or findings which may significantly increase the risk to the volunteer because of participation in the study, and affect the ability of the volunteer to participate in the study or impair interpretation of the study data.

have a history of seizures, epilepsy, encephalopathy, psychosis. history of severe anaphylaxis or allergy to any vaccine component. positive urine pregnancy test result, pregnant, lactating women. medical history of guillain-barré syndrome. have had asthma attacks within 2 years. have severe nasal or oral diseases, such as rhinitis (sinusitis), allergic rhinitis, oral ulcer, throat swelling, etc. bleeding disorder (e.g. protein s or factor deficiency, coagulopathy or platelet disorder). have chronic systematic infection or chronic obstructive pulmonary disease (copd), etc. administration of immunoglobulins and/or any blood products within three months prior to the planned administration of the vaccine candidate. current diagnosis or receiving treatment for tuberculosis or cancer. history of sars-cov-2 infection for less than 3 months. received or plan to receive any vaccines (licensed or investigational), within 14 days before and after study vaccination. have an axillary temperature of > 37.0℃. any other significant diseases, disorders or findings which may significantly increase the risk to the volunteer because of participation in the study, and affect the ability of the volunteer to participate in the study or impair interpretation of the study data.