Immunogenicity and Safety of Meningococcal (A, C, Y and W135) Conjugate Vaccine

Inclusion Criteria: * Subjects who the investigator believes will comply with the requirements of the protocol should be enrolled in the study. * Healthy permanent residence 2 months to 6 years old. * Subjects and parent/guardian able to attend all scheduled visits and comply with all study procedures. * Axillary temperature ≤37.0 ℃. Exclusion Criteria: * History of meningitis infection or vaccination of meningococcal vaccine within the past 6 months. * Allergic history or any SAE after vaccination, such as allergy, urticaria, dyspnea, angioedema, celialgia. * Patients administered with immunosuppressive agents, cytotoxicity factor or corticosteroids in the 6 months preceding the vaccine trial. * Receipt of blood or blood-derived products in the 3 months preceding vaccination * Participation in another clinical study investigating a vaccine, drug in the 30 days preceding vaccination. * Receipt of any live virus vaccine in the 15 days preceding vaccination. * Receipt of any subunit vaccine and inactivated vaccine in the 7 days before vaccination. * Febrile illness (temperature ≥ 38°C) in the 3 days or any acute illness/infection in the 7 days preceding vaccination. * Thrombocytopenia. * History of thyroid gland excision or treatment for thyroid gland disease in last 12 months. * Functional or anatomic asplenia. * History of eclampsia, epilepsy, encephalopathy and mental disease or family disease. * Chronic disease (such as Down syndrome, diabetes, sickle cell anemia or neurologic disease, Guillain-Barre Syndrome). * Known or suspected diseases, including: respiratory system disease, acute infection or active stage of chronic disease, HIV infection of children or mothers, cardiovascular disease, acute hypertension, cancer treatment, skin disease, etc. * Any condition that, in the judgment of investigator, may affect trial assessment.