The purpose of this study is to evaluate Immunogenicity and safety of 15-Valent Pneumococcal Conjugate Vaccine in healthy volunteers aged 2 and 3 months.

Inclusion Criteria:

• Aged above 2 months (minimum to 6 weeks), term (37-42 weeks gestation) and birth weight ≥2.5 kg.
• The guardian understands the vaccination and research procedures, volunteers to participate in the research and sign the informed consent.
• The guardian can follow the clinical research program, will be able to follow up until 3 years after booster immunization and have the ability to use thermometers, scale and fill in diary and contact cards as required.
• There was no history of other live vaccines in the past 14 days and no history of other inactivated vaccines in the seventh day.
• Subaxillary body temperature <=37.0 C.
• Determine health based on medical history, physical examination, and researcher's judgment.

Exclusion Criteria:

• Have been vaccinated a listed or experimental pneumococcal vaccine.
• History of invasive diseases caused by Streptococcus pneumoniae confirmed by bacterial culture in the past.
• In the past, there was any history of vaccination or serious allergy to drugs. In the past, fever of over 39.5 C related to vaccination occurred in biological products for vaccination and prophylaxis.
• History of convulsion, epilepsy, encephalopathy and psychiatry or family history.
• Had abnormal labor (dystocia, device midwifery), history of asphyxia rescue and nerve organ damage.
• History of pathological jaundice confirmed by diagnosis.
• A history of thrombocytopenia or other coagulation disorders with definite diagnosis.
• Human serum gamma globulin injection after birth.
• There are known or suspected immunological abnormalities, including immunosuppressive therapy (radiotherapy, chemotherapy, corticosteroids, antimetabolites, cytotoxic drugs), HIV infection, etc.
• Congenital malformations, severe malnutrition, developmental disorders, genetic defects (e.g. broad bean disease).
• Severe chronic disease, infectious disease, active infection, liver disease, kidney disease, cardiovascular disease, malignant tumor.
• Severe asthma.
• Systemic rash, dermatophytes, skin pus or blister.
• Participation in other drug clinical trials.
• Anything that the researcher considers likely to affect the evaluation of the study.