Study on Immunization Schedule of Beijing Tiantan Biological's Measles-mumps-rubella(MMR) Vaccine

This study will evaluate the immunogenicity and safety of Beijing Tiantan's MMR vaccine in subjects 18 months of age and older.

The MMR vaccine may be administered as a second dose to 4-6 year-old persons with one dose immunization with MMR vaccine or as a first dose to 18 month-old subjects with one dose immunization with MR.

Immune efficacy and safety will be compared among different immunization schedules,including inoculation doses,enhanced immunity age,vaccination interval time.

Antibody persistence of 1 dose of MMR vaccine will be evaluated in this study.

• Measles, mumps and rubella Combined Vaccine, Live (Biological), also known as Beijing Tiantan Biological Products Co., Ltd: Subjects will be inoculated one dose of MMR vaccine and collected blood samples before and after vaccination.

Primary outcomes

• Immunogenicity of the MMR vaccines in terms of antibody concentration [through study completion, an average of 1 year]: For measles virus, seroresponse is defined as post-vaccination anti-measles virus antibody concentration (Ab conc) >200 mIU/mL. For mumps virus, seroresponse is defined as post-vaccination anti-mumps virus Ab conc >100 IU/mL. For rubella virus, seroresponse is defined as post-vaccination anti-rubella virus Ab conc >20 IU/mL.

Sex: All, ages: 18 Months to 6 Years, accepts healthy volunteers

Inclusion Criteria:

* healthy children; 150 subjects 18 months old; 150 subjects 4 years old;300 subjects 5 years old; 150 subjects 6 years old; their guardians signed informed consent;
* undiagnosed as measles, mumps and rubella;
* in good health as determined by the outcome of medical history, physical examination and clinical judgment; suitable to MMR immunization;
* guardians would comply with the requirements of the protocol;
* immunized with MR or measles vaccine(MV) at 8 months old;immunized with MMR at 18 months old(not applicable to subjects 18 months old); unvaccinated by biological products within one month;
* Axillary temperature ≤37℃;
* the local household population or permanent population;

Exclusion Criteria:

* history of allergic disease or reactions likely to be exacerbated by any component of the vaccine(any previous vaccination history of allergies and egg allergy history);
* Current confirmed as acute disease, severe chronic diseases or acute development of chronic diseases;
* Participating in another clinical trial at the same time;

• Jiang Wu, Principal investigator, Beijing Center for Diseases Control and Prevention