Immunogenicity of the Inactivated EV71 Vaccine Combined With Hepatitis B and Group A Meningococcal Vaccine

Inclusion Criteria: * Healthy children aged 6-7 months with no history of vaccination within the past month and normal intelligence. * Healthy individuals determined by researchers after inquiring about medical history and physical examination. * The recipients are able to comply with the requirements of the research protocol and undergo immunogenicity testing. * Individuals without contraindications. * Underarm temperature ≤ 37 ℃. * Obtain informed consent from the recipient's guardian and sign an informed consent form. Exclusion Criteria: * Individuals with any serious illness. * Individuals who are allergic to any ingredient in the research vaccine. * Individuals with a history of neurological symptoms or signs. * Individuals with bleeding constitution or prolonged bleeding time. * Individuals who have had hand, foot, and mouth disease, hepatitis B, and epidemic cerebrospinal meningitis in the past. * Individuals who have received other vaccines or immunoglobulin injections or any investigational drugs within the past 4 weeks. * Infected individuals who have had any acute illness or require systemic antibiotic or antiviral treatment within the past 7 days. * Individuals who have experienced fever (axillary temperature ≥ 38 ℃) within the past 3 days. * Participating in another researcher. * Individuals with a history or family history of allergies, seizures, epilepsy, encephalopathy, and mental illness. * Patients with thrombocytopenia or other coagulation disorders that…