1. within 14 days before vaccination, subjects have been abroad and to villages/communities experienced covid-19 epidemics, and in contact with covid-19 cases or suspected cases. subjects are under isolation observation, or living in the villages/communities with covid-19 cases or suspected cases; 2. confirmed cases, suspected cases or asymptomatic cases with covid-19 (refer to information system of china disease prevention and control); 3. subjects with history of sars virus infection by self-reported; 4. positive in throat swab through rt-pcr; 5. positive in sars-cov-2 antibody test; 6. subjects with history of severe allergic reactions (such as acute anaphylaxis, urticaria, skin eczema, dyspnea, angioneurotic edema or abdominal pain) or allergy to known composition of inactivated sars-cov-2 vaccine; 7. subjects with history of convulsion, epilepsy, encephalopathy or mental illness or family history; 8. subjects with congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; 9. subjects with known or suspected diseases include: severe respiratory diseases, severe cardiovascular diseases, severe liver and kidney diseases, uncontrollable hypertension (systolic pressure \>=140 mmhg, diastolic pressure \>= 90 mmhg; subjects aged \>= 60 years with systolic pressure \>=150 mmhg, diastolic pressure \>=100 mmhg), diabetic complications, malignant tumors, various acute diseases or acute onset of chronic diseases; 10. subjects diagnosed with congenital or acquired immune deficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; 11. subjects with history of coagulation dysfunction (e.g. coagulation factor deficiency, coagulation disease); 12. subjects receiving anti-tb treatment; 13. subjects receiving other research drugs within 6 months before vaccination; 14. subjects receiving immunotherapy or inhibitor therapy within 3 months (consistently oral or infusion for more than 14 days); 15. subjects receiving blood products within 3 months before administration; 16. subjects vaccinated with live attenuated vaccine within 14 days before vaccination; 17. subjects vaccinated with other vaccine within 7 days before vaccination; 18. the researchers shall judge the other conditions which might be not in compliance with the requirements of this clinical trial.

1. within 14 days before vaccination, subjects have been abroad and to villages/communities experienced covid-19 epidemics, and in contact with covid-19 cases or suspected cases. subjects are under isolation observation, or living in the villages/communities with covid-19 cases or suspected cases; 2. confirmed cases, suspected cases or asymptomatic cases with covid-19 (refer to information system of china disease prevention and control); 3. subjects with history of sars virus infection by self-reported; 4. positive in throat swab through rt-pcr; 5. positive in sars-cov-2 antibody test; 6. subjects with history of severe allergic reactions (such as acute anaphylaxis, urticaria, skin eczema, dyspnea, angioneurotic edema or abdominal pain) or allergy to known composition of inactivated sars-cov-2 vaccine; 7. subjects with history of convulsion, epilepsy, encephalopathy or mental illness or family history; 8. subjects with congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; 9. subjects with known or suspected diseases include: severe respiratory diseases, severe cardiovascular diseases, severe liver and kidney diseases, uncontrollable hypertension (systolic pressure \>=140 mmhg, diastolic pressure \>= 90 mmhg; subjects aged \>= 60 years with systolic pressure \>=150 mmhg, diastolic pressure \>=100 mmhg), diabetic complications, malignant tumors, various acute diseases or acute onset of chronic diseases; 10. subjects diagnosed with congenital or acquired immune deficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; 11. subjects with history of coagulation dysfunction (e.g. coagulation factor deficiency, coagulation disease); 12. subjects receiving anti-tb treatment; 13. subjects receiving other research drugs within 6 months before vaccination; 14. subjects receiving immunotherapy or inhibitor therapy within 3 months (consistently oral or infusion for more than 14 days); 15. subjects receiving blood products within 3 months before administration; 16. subjects vaccinated with live attenuated vaccine within 14 days before vaccination; 17. subjects vaccinated with other vaccine within 7 days before vaccination; 18. the researchers shall judge the other conditions which might be not in compliance with the requirements of this clinical trial.

within 14 days before vaccination, subjects have been abroad and to villages/communities experienced covid-19 epidemics, and in contact with covid-19 cases or suspected cases. subjects are under isolation observation, or living in the villages/communities with covid-19 cases or suspected cases; confirmed cases, suspected cases or asymptomatic cases with covid-19 (refer to information system of china disease prevention and control); subjects with history of sars virus infection by self-reported; positive in throat swab through rt-pcr; positive in sars-cov-2 antibody test; subjects with history of severe allergic reactions (such as acute anaphylaxis, urticaria, skin eczema, dyspnea, angioneurotic edema or abdominal pain) or allergy to known composition of inactivated sars-cov-2 vaccine; subjects with history of convulsion, epilepsy, encephalopathy or mental illness or family history; subjects with congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; subjects with known or suspected diseases include: severe respiratory diseases, severe cardiovascular diseases, severe liver and kidney diseases, uncontrollable hypertension (systolic pressure >=140 mmhg, diastolic pressure >= 90 mmhg; subjects aged >= 60 years with systolic pressure >=150 mmhg, diastolic pressure >=100 mmhg), diabetic complications, malignant tumors, various acute diseases or acute onset of chronic diseases; subjects diagnosed with congenital or acquired immune deficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; subjects with history of coagulation dysfunction (e.g. coagulation factor deficiency, coagulation disease); subjects receiving anti-tb treatment; subjects receiving other research drugs within 6 months before vaccination; subjects receiving immunotherapy or inhibitor therapy within 3 months (consistently oral or infusion for more than 14 days); subjects receiving blood products within 3 months before administration; subjects vaccinated with live attenuated vaccine within 14 days before vaccination; subjects vaccinated with other vaccine within 7 days before vaccination; the researchers shall judge the other conditions which might be not in compliance with the requirements of this clinical trial.

within 14 days before vaccination, subjects have been abroad and to villages/communities experienced covid-19 epidemics, and in contact with covid-19 cases or suspected cases. subjects are under isolation observation, or living in the villages/communities with covid-19 cases or suspected cases; confirmed cases, suspected cases or asymptomatic cases with covid-19 (refer to information system of china disease prevention and control); subjects with history of sars virus infection by self-reported; positive in throat swab through rt-pcr; positive in sars-cov-2 antibody test; subjects with history of severe allergic reactions (such as acute anaphylaxis, urticaria, skin eczema, dyspnea, angioneurotic edema or abdominal pain) or allergy to known composition of inactivated sars-cov-2 vaccine; subjects with history of convulsion, epilepsy, encephalopathy or mental illness or family history; subjects with congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; subjects with known or suspected diseases include: severe respiratory diseases, severe cardiovascular diseases, severe liver and kidney diseases, uncontrollable hypertension (systolic pressure >=140 mmhg, diastolic pressure >= 90 mmhg; subjects aged >= 60 years with systolic pressure >=150 mmhg, diastolic pressure >=100 mmhg), diabetic complications, malignant tumors, various acute diseases or acute onset of chronic diseases; subjects diagnosed with congenital or acquired immune deficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; subjects with history of coagulation dysfunction (e.g. coagulation factor deficiency, coagulation disease); subjects receiving anti-tb treatment; subjects receiving other research drugs within 6 months before vaccination; subjects receiving immunotherapy or inhibitor therapy within 3 months (consistently oral or infusion for more than 14 days); subjects receiving blood products within 3 months before administration; subjects vaccinated with live attenuated vaccine within 14 days before vaccination; subjects vaccinated with other vaccine within 7 days before vaccination; the researchers shall judge the other conditions which might be not in compliance with the requirements of this clinical trial.

1. within 14 days before vaccination, subjects have been abroad and to villages/communities experienced covid-19 epidemics, and in contact with covid-19 cases or suspected cases. subjects are under isolation observation, or living in the villages/communities with covid-19 cases or suspected cases; 2. confirmed cases, suspected cases or asymptomatic cases with covid-19 (refer to information system of china disease prevention and control); 3. subjects with history of sars virus infection by self-reported; 4. positive in throat swab through rt-pcr; 5. positive in sars-cov-2 antibody test; 6. subjects with history of severe allergic reactions (such as acute anaphylaxis, urticaria, skin eczema, dyspnea, angioneurotic edema or abdominal pain) or allergy to known composition of inactivated sars-cov-2 vaccine; 7. subjects with history of convulsion, epilepsy, encephalopathy or mental illness or family history; 8. subjects with congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; 9. subjects with known or suspected diseases include: severe respiratory diseases, severe cardiovascular diseases, severe liver and kidney diseases, uncontrollable hypertension (systolic pressure >=140 mmhg, diastolic pressure >= 90 mmhg; subjects aged >= 60 years with systolic pressure >=150 mmhg, diastolic pressure >=100 mmhg), diabetic complications, malignant tumors, various acute diseases or acute onset of chronic diseases; 10. subjects diagnosed with congenital or acquired immune deficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; 11. subjects with history of coagulation dysfunction (e.g. coagulation factor deficiency, coagulation disease); 12. subjects receiving anti-tb treatment; 13. subjects receiving other research drugs within 6 months before vaccination; 14. subjects receiving immunotherapy or inhibitor therapy within 3 months (consistently oral or infusion for more than 14 days); 15. subjects receiving blood products within 3 months before administration; 16. subjects vaccinated with live attenuated vaccine within 14 days before vaccination; 17. subjects vaccinated with other vaccine within 7 days before vaccination; 18. the researchers shall judge the other conditions which might be not in compliance with the requirements of this clinical trial.

1. within 14 days before vaccination, subjects have been abroad and to villages/communities experienced covid-19 epidemics, and in contact with covid-19 cases or suspected cases. subjects are under isolation observation, or living in the villages/communities with covid-19 cases or suspected cases; 2. confirmed cases, suspected cases or asymptomatic cases with covid-19 (refer to information system of china disease prevention and control); 3. subjects with history of sars virus infection by self-reported; 4. positive in throat swab through rt-pcr; 5. positive in sars-cov-2 antibody test; 6. subjects with history of severe allergic reactions (such as acute anaphylaxis, urticaria, skin eczema, dyspnea, angioneurotic edema or abdominal pain) or allergy to known composition of inactivated sars-cov-2 vaccine; 7. subjects with history of convulsion, epilepsy, encephalopathy or mental illness or family history; 8. subjects with congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; 9. subjects with known or suspected diseases include: severe respiratory diseases, severe cardiovascular diseases, severe liver and kidney diseases, uncontrollable hypertension (systolic pressure >=140 mmhg, diastolic pressure >= 90 mmhg; subjects aged >= 60 years with systolic pressure >=150 mmhg, diastolic pressure >=100 mmhg), diabetic complications, malignant tumors, various acute diseases or acute onset of chronic diseases; 10. subjects diagnosed with congenital or acquired immune deficiency, hiv infection, lymphoma, leukemia or other autoimmune diseases; 11. subjects with history of coagulation dysfunction (e.g. coagulation factor deficiency, coagulation disease); 12. subjects receiving anti-tb treatment; 13. subjects receiving other research drugs within 6 months before vaccination; 14. subjects receiving immunotherapy or inhibitor therapy within 3 months (consistently oral or infusion for more than 14 days); 15. subjects receiving blood products within 3 months before administration; 16. subjects vaccinated with live attenuated vaccine within 14 days before vaccination; 17. subjects vaccinated with other vaccine within 7 days before vaccination; 18. the researchers shall judge the other conditions which might be not in compliance with the requirements of this clinical trial.