The Phase IVd of Inactivated Enterovirus 71 Vaccine

Inclusion Criteria: * Healthy subjects (6-71 months old children) as established by medical history and clinical examination * The subjects' legal guardian must be aware of this vaccines * The subjects' legal guardian voluntarily participate in the study and signed Informed Consent Form * Subjects with temperature ≤ 37.0 ℃ * The subjects' legal guardian with the ability and objective to comply with the requirements of the protocol * Persist for a 14-month visit (and receive blood, stool (or specimens by means of a swab) tests according to program requirements in immunogenicity observation group) Exclusion Criteria: * Allergy or serious side-effects to a vaccine or any ingredient of vaccine * Epilepsy, seizures, convulsions, neurological illness * Congenital or hereditary immunodeficiency * Autoimmune disease * Asthma, thyroidectomy, angioneurotic edema, diabetes or cancer * Asplenia, functional asplenia, and any circumstances leading to the asplenia or splenectomy * Clinical diagnosis of coagulopathy (such as clotting factor deficiency, coagulation disorders, platelet abnormalities), significant bruising or blood clotting disorder * Acute illness or acute exacerbation of chronic disease in last 7 days * Any prior administration of immunodepressant or corticosteroids in last 6 months * Any prior administration of blood products in last 3 months * Any prior administration of live-attenuated vaccine in last 15 days * Any prior administration of subunit or inactivated vaccines…