1. contraindications to commonly used vaccines; 2. history of allergy to any vaccines or drug; 3. received any vaccine within 1 month before the vaccination； 4. serious diseases required to be excluded, including but not limited to history of diseases in nervous system, cardiovascular system, blood and lymphatic system, immune system, kidney, liver, gastrointestinal tract, respiratory system, metabolism, bones and other systems, and a history of malignant tumors; 5. before immunizing the investigational vaccine, those who developed acute disease within 2 weeks, or had symptoms of fever or upper respiratory tract infection within 7 days; 6. those who have a hereditary bleeding tendency or blood coagulation dysfunction, or a history of thrombosis or hemorrhagic disease； 7. surgical removal of whole or part of spleen for any reason； 8. those who have undergone surgery within 3 months before signing the icf or those who plan to undergo surgery during or within 3 months after completion of the trial (including plastic surgery, dental and oral surgery); 9. those who donated or lost blood (≥400 ml) in the past 3 months, who received blood transfusion or use of blood products, or who plan blood donation during the trial; 10. those who received other investigational or unregistered products (drugs, vaccines, biological product or devices) in the past 3 months before signing the icf, or plan to use them during the study. 11. those who received immunosuppressant therapy within 6 months before signing the icf, such as long-term systemic glucocorticoid treatment (with systemic glucocorticoid therapy for more than 2 consecutive weeks within 6 months, such as prednisone or similar drugs), but local administration is permitted (such as ointment, eye drops, inhalants, or nasal spray). the local administration should not exceed the recommended dose in the package insert or have any signs of systemic exposure; 12. participants cannot meet the criteria through the comprehensive physical examination, mainly including: - abnormal vital signs with clinical significance (awakening heart rate \<55 beats/min or \>100 beats/min, systolic blood pressure ≥140 millimetre of mercury (mmhg) or diastolic blood pressure ≥90mmhg); - those who tested positive for type 1 or type 2 human immunodeficiency virus (hiv-1/2) antibody, or sars-cov-2 nucleic acid; 13. history of covid-19; 14. participants who have a positive pregnancy test, or are breastfeeding, or planning pregnancy, or plan to donate sperm or eggs within 12 months from the screening period to the whole-course immunization; 15. participants who are considered as inappropriate for the trial by investigators. 16. suspected or known current alcohol or drug dependency.

1. contraindications to commonly used vaccines; 2. history of allergy to any vaccines or drug; 3. received any vaccine within 1 month before the vaccination； 4. serious diseases required to be excluded, including but not limited to history of diseases in nervous system, cardiovascular system, blood and lymphatic system, immune system, kidney, liver, gastrointestinal tract, respiratory system, metabolism, bones and other systems, and a history of malignant tumors; 5. before immunizing the investigational vaccine, those who developed acute disease within 2 weeks, or had symptoms of fever or upper respiratory tract infection within 7 days; 6. those who have a hereditary bleeding tendency or blood coagulation dysfunction, or a history of thrombosis or hemorrhagic disease； 7. surgical removal of whole or part of spleen for any reason； 8. those who have undergone surgery within 3 months before signing the icf or those who plan to undergo surgery during or within 3 months after completion of the trial (including plastic surgery, dental and oral surgery); 9. those who donated or lost blood (≥400 ml) in the past 3 months, who received blood transfusion or use of blood products, or who plan blood donation during the trial; 10. those who received other investigational or unregistered products (drugs, vaccines, biological product or devices) in the past 3 months before signing the icf, or plan to use them during the study. 11. those who received immunosuppressant therapy within 6 months before signing the icf, such as long-term systemic glucocorticoid treatment (with systemic glucocorticoid therapy for more than 2 consecutive weeks within 6 months, such as prednisone or similar drugs), but local administration is permitted (such as ointment, eye drops, inhalants, or nasal spray). the local administration should not exceed the recommended dose in the package insert or have any signs of systemic exposure; 12. participants cannot meet the criteria through the comprehensive physical examination, mainly including: - abnormal vital signs with clinical significance (awakening heart rate \<55 beats/min or \>100 beats/min, systolic blood pressure ≥140 millimetre of mercury (mmhg) or diastolic blood pressure ≥90mmhg); - those who tested positive for type 1 or type 2 human immunodeficiency virus (hiv-1/2) antibody, or sars-cov-2 nucleic acid; 13. history of covid-19; 14. participants who have a positive pregnancy test, or are breastfeeding, or planning pregnancy, or plan to donate sperm or eggs within 12 months from the screening period to the whole-course immunization; 15. participants who are considered as inappropriate for the trial by investigators. 16. suspected or known current alcohol or drug dependency.

contraindications to commonly used vaccines; history of allergy to any vaccines or drug; received any vaccine within 1 month before the vaccination； serious diseases required to be excluded, including but not limited to history of diseases in nervous system, cardiovascular system, blood and lymphatic system, immune system, kidney, liver, gastrointestinal tract, respiratory system, metabolism, bones and other systems, and a history of malignant tumors; before immunizing the investigational vaccine, those who developed acute disease within 2 weeks, or had symptoms of fever or upper respiratory tract infection within 7 days; those who have a hereditary bleeding tendency or blood coagulation dysfunction, or a history of thrombosis or hemorrhagic disease； surgical removal of whole or part of spleen for any reason； those who have undergone surgery within 3 months before signing the icf or those who plan to undergo surgery during or within 3 months after completion of the trial (including plastic surgery, dental and oral surgery); those who donated or lost blood (≥400 ml) in the past 3 months, who received blood transfusion or use of blood products, or who plan blood donation during the trial; those who received other investigational or unregistered products (drugs, vaccines, biological product or devices) in the past 3 months before signing the icf, or plan to use them during the study. those who received immunosuppressant therapy within 6 months before signing the icf, such as long-term systemic glucocorticoid treatment (with systemic glucocorticoid therapy for more than 2 consecutive weeks within 6 months, such as prednisone or similar drugs), but local administration is permitted (such as ointment, eye drops, inhalants, or nasal spray). the local administration should not exceed the recommended dose in the package insert or have any signs of systemic exposure; participants cannot meet the criteria through the comprehensive physical examination, mainly including: - abnormal vital signs with clinical significance (awakening heart rate <55 beats/min or >100 beats/min, systolic blood pressure ≥140 millimetre of mercury (mmhg) or diastolic blood pressure ≥90mmhg); - those who tested positive for type 1 or type 2 human immunodeficiency virus (hiv-1/2) antibody, or sars-cov-2 nucleic acid; history of covid-19; participants who have a positive pregnancy test, or are breastfeeding, or planning pregnancy, or plan to donate sperm or eggs within 12 months from the screening period to the whole-course immunization; participants who are considered as inappropriate for the trial by investigators. suspected or known current alcohol or drug dependency.

contraindications to commonly used vaccines; history of allergy to any vaccines or drug; received any vaccine within 1 month before the vaccination； serious diseases required to be excluded, including but not limited to history of diseases in nervous system, cardiovascular system, blood and lymphatic system, immune system, kidney, liver, gastrointestinal tract, respiratory system, metabolism, bones and other systems, and a history of malignant tumors; before immunizing the investigational vaccine, those who developed acute disease within 2 weeks, or had symptoms of fever or upper respiratory tract infection within 7 days; those who have a hereditary bleeding tendency or blood coagulation dysfunction, or a history of thrombosis or hemorrhagic disease； surgical removal of whole or part of spleen for any reason； those who have undergone surgery within 3 months before signing the icf or those who plan to undergo surgery during or within 3 months after completion of the trial (including plastic surgery, dental and oral surgery); those who donated or lost blood (≥400 ml) in the past 3 months, who received blood transfusion or use of blood products, or who plan blood donation during the trial; those who received other investigational or unregistered products (drugs, vaccines, biological product or devices) in the past 3 months before signing the icf, or plan to use them during the study. those who received immunosuppressant therapy within 6 months before signing the icf, such as long-term systemic glucocorticoid treatment (with systemic glucocorticoid therapy for more than 2 consecutive weeks within 6 months, such as prednisone or similar drugs), but local administration is permitted (such as ointment, eye drops, inhalants, or nasal spray). the local administration should not exceed the recommended dose in the package insert or have any signs of systemic exposure; participants cannot meet the criteria through the comprehensive physical examination, mainly including: - abnormal vital signs with clinical significance (awakening heart rate <55 beats/min or >100 beats/min, systolic blood pressure ≥140 millimetre of mercury (mmhg) or diastolic blood pressure ≥90mmhg); - those who tested positive for type 1 or type 2 human immunodeficiency virus (hiv-1/2) antibody, or sars-cov-2 nucleic acid; history of covid-19; participants who have a positive pregnancy test, or are breastfeeding, or planning pregnancy, or plan to donate sperm or eggs within 12 months from the screening period to the whole-course immunization; participants who are considered as inappropriate for the trial by investigators. suspected or known current alcohol or drug dependency.

1. contraindications to commonly used vaccines; 2. history of allergy to any vaccines or drug; 3. received any vaccine within 1 month before the vaccination； 4. serious diseases required to be excluded, including but not limited to history of diseases in nervous system, cardiovascular system, blood and lymphatic system, immune system, kidney, liver, gastrointestinal tract, respiratory system, metabolism, bones and other systems, and a history of malignant tumors; 5. before immunizing the investigational vaccine, those who developed acute disease within 2 weeks, or had symptoms of fever or upper respiratory tract infection within 7 days; 6. those who have a hereditary bleeding tendency or blood coagulation dysfunction, or a history of thrombosis or hemorrhagic disease； 7. surgical removal of whole or part of spleen for any reason； 8. those who have undergone surgery within 3 months before signing the icf or those who plan to undergo surgery during or within 3 months after completion of the trial (including plastic surgery, dental and oral surgery); 9. those who donated or lost blood (≥400 ml) in the past 3 months, who received blood transfusion or use of blood products, or who plan blood donation during the trial; 10. those who received other investigational or unregistered products (drugs, vaccines, biological product or devices) in the past 3 months before signing the icf, or plan to use them during the study. 11. those who received immunosuppressant therapy within 6 months before signing the icf, such as long-term systemic glucocorticoid treatment (with systemic glucocorticoid therapy for more than 2 consecutive weeks within 6 months, such as prednisone or similar drugs), but local administration is permitted (such as ointment, eye drops, inhalants, or nasal spray). the local administration should not exceed the recommended dose in the package insert or have any signs of systemic exposure; 12. participants cannot meet the criteria through the comprehensive physical examination, mainly including: - abnormal vital signs with clinical significance (awakening heart rate <55 beats/min or >100 beats/min, systolic blood pressure ≥140 millimetre of mercury (mmhg) or diastolic blood pressure ≥90mmhg); - those who tested positive for type 1 or type 2 human immunodeficiency virus (hiv-1/2) antibody, or sars-cov-2 nucleic acid; 13. history of covid-19; 14. participants who have a positive pregnancy test, or are breastfeeding, or planning pregnancy, or plan to donate sperm or eggs within 12 months from the screening period to the whole-course immunization; 15. participants who are considered as inappropriate for the trial by investigators. 16. suspected or known current alcohol or drug dependency.

1. contraindications to commonly used vaccines; 2. history of allergy to any vaccines or drug; 3. received any vaccine within 1 month before the vaccination； 4. serious diseases required to be excluded, including but not limited to history of diseases in nervous system, cardiovascular system, blood and lymphatic system, immune system, kidney, liver, gastrointestinal tract, respiratory system, metabolism, bones and other systems, and a history of malignant tumors; 5. before immunizing the investigational vaccine, those who developed acute disease within 2 weeks, or had symptoms of fever or upper respiratory tract infection within 7 days; 6. those who have a hereditary bleeding tendency or blood coagulation dysfunction, or a history of thrombosis or hemorrhagic disease； 7. surgical removal of whole or part of spleen for any reason； 8. those who have undergone surgery within 3 months before signing the icf or those who plan to undergo surgery during or within 3 months after completion of the trial (including plastic surgery, dental and oral surgery); 9. those who donated or lost blood (≥400 ml) in the past 3 months, who received blood transfusion or use of blood products, or who plan blood donation during the trial; 10. those who received other investigational or unregistered products (drugs, vaccines, biological product or devices) in the past 3 months before signing the icf, or plan to use them during the study. 11. those who received immunosuppressant therapy within 6 months before signing the icf, such as long-term systemic glucocorticoid treatment (with systemic glucocorticoid therapy for more than 2 consecutive weeks within 6 months, such as prednisone or similar drugs), but local administration is permitted (such as ointment, eye drops, inhalants, or nasal spray). the local administration should not exceed the recommended dose in the package insert or have any signs of systemic exposure; 12. participants cannot meet the criteria through the comprehensive physical examination, mainly including: - abnormal vital signs with clinical significance (awakening heart rate <55 beats/min or >100 beats/min, systolic blood pressure ≥140 millimetre of mercury (mmhg) or diastolic blood pressure ≥90mmhg); - those who tested positive for type 1 or type 2 human immunodeficiency virus (hiv-1/2) antibody, or sars-cov-2 nucleic acid; 13. history of covid-19; 14. participants who have a positive pregnancy test, or are breastfeeding, or planning pregnancy, or plan to donate sperm or eggs within 12 months from the screening period to the whole-course immunization; 15. participants who are considered as inappropriate for the trial by investigators. 16. suspected or known current alcohol or drug dependency.