Safety and Immunogenicity Study of Inactivated Vaccine for Prevention of SARS-CoV-2 Infection(COVID-19)

Inclusion Criteria: * Healthy adults aged ≥60 years; * Be able to understand and sign the informed consent voluntarily; * Provide legal identification; Exclusion Criteria: * Travel / residence history of Wuhan city and surrounding areas or other communities with case reports within 14 days prior to the enrolment; * Contact with SARS-CoV-2 infected persons (positive for nucleic acid detection) within 14 days prior to the enrolment; * Contact patients with fever or respiratory symptoms from Wuhan city and surrounding areas, or from communities with case reports within 14 days prior to the enrolment; * Two or more cases of fever and / or respiratory symptoms in a small contact area of subjects, such as family, office, school class or other places within 14 days prior to the enrolment; * History of SARS; * History of SARS-CoV-2 infection; * History of asthma, allergy to vaccines or vaccine ingredients, and serious adverse reactions to vaccines, such as urticaria, dyspnea, angioneuroedema; * Congenital malformation or developmental disorder, genetic defect, severe malnutrition, etc; * Autoimmune disease or immunodeficiency / immunosuppression; * Serious chronic disease, serious cardiovascular disease, hypertension and diabetes that cannot be controlled by drugs, hepatorenal disease, malignant tumor, etc; * Serious nervous system disease (epilepsy, convulsion or convulsion) or psychosis; * Thyroid disease or history of thyroidectomy, asplenia, functional asplenia, asplenia or splenectomy resulting from any condition; * Diagnosed abnormal blood coagulation function (eg, lack of blood coagulation factors, blood coagulopathy, abnormal platelets) or obvious bruising or blood coagulation; * Immunosuppressive therapy, cytotoxic therapy, inhaled corticosteroids (excluding allergic rhinitis corticosteroid spray therapy, acute non-complicated dermatitis superficial corticosteroid therapy) in the past 6 months; * Long history of alcohol or drug abuse; * Receipt of blood products in the past 3 months; * Receipt of other investigational drugs in the past 30 days; * Receipt of attenuated live vaccines in the past 14 days; * Receipt of inactivated or subunit vaccines in the past 7 days; * Acute diseases or acute exacerbation of chronic diseases in the past 7 days; * Axillary temperature \>37.0°C; * According to the investigator's judgment, the subject has any other factors that are not suitable for the clinical trial.