confirmed cases, suspected cases or asymptomatic cases of covid-19; with a history of sars and mers infection (self-report, on-site inquiry); has vaccinated with any vaccine other than one or more doses of cnbg inactivated covid-19 vaccine; axillary temperature ≥ 37.3 ℃ (forehead temperature ≥ 37.8 ℃); previous severe allergic reactions to vaccination (such as acute allergic reactions, urticaria, dyspnea, angioneurotic edema or abdominal pain) or allergy to known components of recombinant covid-19 vaccine; allergic to any component of the study vaccine (e.g. aluminum, histidine, etc.) known or suspected diseases include：severe respiratory diseases, severe liver and kidney diseases, hypertension (systolic blood pressure ≥ 150 mmhg, diastolic blood pressure ≥ 90 mmhg), diabetic complications, malignant tumors, various acute diseases or acute attacks of chronic diseases; has been diagnosed with congenital or acquired immunodeficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; has a history of convulsions, epilepsy, encephalopathy，long term history of alcohol and drug abuse, history of thyroidectomy, infectious diseasesor mental illness or family history（lineal）; with congenital malformation or developmental disorder, genetic defect, severe malnutrition, etc.; has a history of coagulation dysfunction (e.g. coagulation factors deficiency and coagulation diseases); absence of spleen or splenectomy, functional absence of spleen caused by any condition anti -tb (tb) treatment is under way. patients receiving immunoenhancement or inhibitor therapy within 3 months (continuous oral or iv administration for more than 14 days); received other vaccines within 14 days before vaccination； received blood products before within 3 months before vaccination; received other investigational drugs within 6 months before vaccination; plan to move before the end of the study or leave the local area for a long time during the scheduled study visit other circumstances judged by investigators that are not suitable for this clinical trial

confirmed cases, suspected cases or asymptomatic cases of covid-19; with a history of sars and mers infection (self-report, on-site inquiry); has vaccinated with any vaccine other than one or more doses of cnbg inactivated covid-19 vaccine; axillary temperature ≥ 37.3 ℃ (forehead temperature ≥ 37.8 ℃); previous severe allergic reactions to vaccination (such as acute allergic reactions, urticaria, dyspnea, angioneurotic edema or abdominal pain) or allergy to known components of recombinant covid-19 vaccine; allergic to any component of the study vaccine (e.g. aluminum, histidine, etc.) known or suspected diseases include：severe respiratory diseases, severe liver and kidney diseases, hypertension (systolic blood pressure ≥ 150 mmhg, diastolic blood pressure ≥ 90 mmhg), diabetic complications, malignant tumors, various acute diseases or acute attacks of chronic diseases; has been diagnosed with congenital or acquired immunodeficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; has a history of convulsions, epilepsy, encephalopathy，long term history of alcohol and drug abuse, history of thyroidectomy, infectious diseasesor mental illness or family history（lineal）; with congenital malformation or developmental disorder, genetic defect, severe malnutrition, etc.; has a history of coagulation dysfunction (e.g. coagulation factors deficiency and coagulation diseases); absence of spleen or splenectomy, functional absence of spleen caused by any condition anti -tb (tb) treatment is under way. patients receiving immunoenhancement or inhibitor therapy within 3 months (continuous oral or iv administration for more than 14 days); received other vaccines within 14 days before vaccination； received blood products before within 3 months before vaccination; received other investigational drugs within 6 months before vaccination; plan to move before the end of the study or leave the local area for a long time during the scheduled study visit other circumstances judged by investigators that are not suitable for this clinical trial

- confirmed cases, suspected cases or asymptomatic cases of covid-19; - with a history of sars and mers infection (self-report, on-site inquiry); - has vaccinated with any vaccine other than one or more doses of cnbg inactivated covid-19 vaccine; - axillary temperature ≥ 37.3 ℃ (forehead temperature ≥ 37.8 ℃); - previous severe allergic reactions to vaccination (such as acute allergic reactions, urticaria, dyspnea, angioneurotic edema or abdominal pain) or allergy to known components of recombinant covid-19 vaccine; - allergic to any component of the study vaccine (e.g. aluminum, histidine, etc.) - known or suspected diseases include：severe respiratory diseases, severe liver and kidney diseases, hypertension (systolic blood pressure ≥ 150 mmhg, diastolic blood pressure ≥ 90 mmhg), diabetic complications, malignant tumors, various acute diseases or acute attacks of chronic diseases; - has been diagnosed with congenital or acquired immunodeficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; - has a history of convulsions, epilepsy, encephalopathy，long term history of alcohol and drug abuse, history of thyroidectomy, infectious diseasesor mental illness or family history（lineal）; - with congenital malformation or developmental disorder, genetic defect, severe malnutrition, etc.; - has a history of coagulation dysfunction (e.g. coagulation factors deficiency and coagulation diseases); - absence of spleen or splenectomy, functional absence of spleen caused by any condition - anti -tb (tb) treatment is under way. - patients receiving immunoenhancement or inhibitor therapy within 3 months (continuous oral or iv administration for more than 14 days); - received blood products before within 3 months before vaccination; - received other investigational drugs within 6 months before vaccination; - plan to move before the end of the study or leave the local area for a long time during the scheduled study visit - other circumstances judged by investigators that are not suitable for this clinical trial

- confirmed cases, suspected cases or asymptomatic cases of covid-19; - with a history of sars and mers infection (self-report, on-site inquiry); - has vaccinated with any vaccine other than one or more doses of cnbg inactivated covid-19 vaccine; - axillary temperature ≥ 37.3 ℃ (forehead temperature ≥ 37.8 ℃); - previous severe allergic reactions to vaccination (such as acute allergic reactions, urticaria, dyspnea, angioneurotic edema or abdominal pain) or allergy to known components of recombinant covid-19 vaccine; - allergic to any component of the study vaccine (e.g. aluminum, histidine, etc.) - known or suspected diseases include：severe respiratory diseases, severe liver and kidney diseases, hypertension (systolic blood pressure ≥ 150 mmhg, diastolic blood pressure ≥ 90 mmhg), diabetic complications, malignant tumors, various acute diseases or acute attacks of chronic diseases; - has been diagnosed with congenital or acquired immunodeficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; - has a history of convulsions, epilepsy, encephalopathy，long term history of alcohol and drug abuse, history of thyroidectomy, infectious diseasesor mental illness or family history（lineal）; - with congenital malformation or developmental disorder, genetic defect, severe malnutrition, etc.; - has a history of coagulation dysfunction (e.g. coagulation factors deficiency and coagulation diseases); - absence of spleen or splenectomy, functional absence of spleen caused by any condition - anti -tb (tb) treatment is under way. - patients receiving immunoenhancement or inhibitor therapy within 3 months (continuous oral or iv administration for more than 14 days); - received blood products before within 3 months before vaccination; - received other investigational drugs within 6 months before vaccination; - plan to move before the end of the study or leave the local area for a long time during the scheduled study visit - other circumstances judged by investigators that are not suitable for this clinical trial