1) Axillary temperature > 37.0 degree C, 2) Patients with Corona Virus Disease 2019 (COVID-19), severe acute respiratory syndrome (SARS) or Middle East respiratory syndrome (MERS). 3) Patients with history of COVID-19 vaccines or other candidate vaccines (except sequential subgroup), 4) Pregnant (i.e. positive urine pregnancy test) or breastfeeding during the vaccination period. If pregnant after all vaccination, the follow-up study will not be excluded and will be followed up to the end of delivery, 5) Those who had fever (axillary temperature >=38.0 degree C) within 3 days before vaccination or had any acute disease in the past 5 days and needed systemic application of antibiotics or antiviral drugs (including but not limited to the use of anti influenza virus drugs such as Tamiflu, Relenza, Symmetrel or flumadine), 6) Patients with immune deficiency diseases, important organs include primary diseases, cancer, immune diseases (including Guillain Barre syndrome, systemic lupus erythematosus, rheumatoid arthritis, splenectomy or splenectomy caused by any condition, and other immune diseases that researchers believe may have adverse effects on immune response), etc, 7) Long-term(lasting more than 14 days) use of immunosuppressants and other immunoregulatory drugs or systemic use of corticosteroids (Topical ointment, eye drops, inhalers, etc. are allowed, but nasal spray is not included ) within 6 months before vaccination 8) History of hemorrhagic disease (such as factor deficiency, coagulation disorder or platelet disorder), obvious bleeding or bruise after venipuncture, 9) Received immunoglobulin and/or blood preparations within 3 months before vaccination, or plan to use them during the study period, 10) Had received subunit or inactivated vaccine within 14 days before vaccination, or had received live attenuated vaccine within 28 days before vaccination, 11) Those who have received other research drugs or vaccines within one month before vaccination, or plan to use other research drugs or vaccines during the research period, 12) Received any intranasal medication or nasal surgery within 7 days before vaccination, 13) Those with a history of severe allergy, including severe adverse reactions such as allergy, urticaria, dyspnea, angioneurotic edema, etc., or allergic to any component of the vaccine used in this trial, 14) After inquiring about the subjects' medical history and related physical examination, the researcher judged that various medical, psychological, social, occupational or other conditions may affect the progress of clinical research.

1) Axillary temperature > 37.0 degree C, 2) Patients with Corona Virus Disease 2019 (COVID-19), severe acute respiratory syndrome (SARS) or Middle East respiratory syndrome (MERS). 3) Patients with history of COVID-19 vaccines or other candidate vaccines (except sequential subgroup), 4) Pregnant (i.e. positive urine pregnancy test) or breastfeeding during the vaccination period. If pregnant after all vaccination, the follow-up study will not be excluded and will be followed up to the end of delivery, 5) Those who had fever (axillary temperature >=38.0 degree C) within 3 days before vaccination or had any acute disease in the past 5 days and needed systemic application of antibiotics or antiviral drugs (including but not limited to the use of anti influenza virus drugs such as Tamiflu, Relenza, Symmetrel or flumadine), 6) Patients with immune deficiency diseases, important organs include primary diseases, cancer, immune diseases (including Guillain Barre syndrome, systemic lupus erythematosus, rheumatoid arthritis, splenectomy or splenectomy caused by any condition, and other immune diseases that researchers believe may have adverse effects on immune response), etc, 7) Long-term(lasting more than 14 days) use of immunosuppressants and other immunoregulatory drugs or systemic use of corticosteroids (Topical ointment, eye drops, inhalers, etc. are allowed, but nasal spray is not included ) within 6 months before vaccination 8) History of hemorrhagic disease (such as factor deficiency, coagulation disorder or platelet disorder), obvious bleeding or bruise after venipuncture, 9) Received immunoglobulin and/or blood preparations within 3 months before vaccination, or plan to use them during the study period, 10) Had received subunit or inactivated vaccine within 14 days before vaccination, or had received live attenuated vaccine within 28 days before vaccination, 11) Those who have received other research drugs or vaccines within one month before vaccination, or plan to use other research drugs or vaccines during the research period, 12) Received any intranasal medication or nasal surgery within 7 days before vaccination, 13) Those with a history of severe allergy, including severe adverse reactions such as allergy, urticaria, dyspnea, angioneurotic edema, etc., or allergic to any component of the vaccine used in this trial, 14) After inquiring about the subjects' medical history and related physical examination, the researcher judged that various medical, psychological, social, occupational or other conditions may affect the progress of clinical research.