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

Inclusion Criteria: * Healthy adults aged 18-59 years; * Proven legal identity; * Participants should be capable of understanding the informed consent form, and such form should be signed prior to enrolment ; Exclusion Criteria: * Travel history / residence history of Wuhan city and surrounding areas, or other communities with case reports within 14 days; * History of contact with a SARS-CoV-2 infection (positive in nucleic acid test) within 14 days; * Have contacted patients with fever or respiratory symptoms from Wuhan and surrounding areas, or from communities with case reports within 14 days; * Have contacted patients with fever or respiratory symptoms from Wuhan and surrounding areas, or from communities with case reports within 14 days; * Self-reported history of SARS; * Self-reported history of new coronavirus infection; * Positive in serum antibodies (IgG or IgM) screening of COVID-19; * Positive in nasopharyngeal swabs or anal swabs through RT-PCR; * Women who are breastfeeding, pregnant or planning to become pregnant during the study period; * BMI≥35 kg/m2; * History of asthma, history of allergy to the vaccine or vaccine components, or serious adverse reactions to the vaccine, such as urticaria, dyspnea, and angioedema; * Congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; * Autoimmune disease or immunodeficiency / immunosuppression; * Suffering from severe chronic diseases, severe cardiovascular diseases, hypertension and diabetes that cannot be controlled by drugs, liver and kidney diseases, malignant tumors, etc.; * Severe neurological disease (epilepsy, convulsions or convulsions) or mental illness; * Thyroid disease or history of thyroidectomy, spleenlessness, functional spleenlessness, spleenlessness 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; * Abnormal laboratory test results in the physical examination such as clinically significant abnormal hematology and biochemistry beyond the reference value range (only applicable to Phase I clinical trials); * History of alcohol or drug abuse; * Receipt of blood products within 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; * Attacks of acute diseases or 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 participating in the clinical trial.