Immunogenicity and Reactogenicity of a Trivalent MMR (Trivivac) in Healthy Infants

Inclusion Criteria: 1. Infants aged 9-14 months whose parents/LAR give written informed consent prior to the study entry. 2. Infants with good health as determined by: Medical history, Physical examination, Clinical judgment of the investigator 3. Infants who are not seroprotected against MMR virus by virtue of previous immunization and/or proven prior infection. Exclusion Criteria: 1. Children whom parents or LAR are unwilling or unable to give written informed consent to participate in the study. 2. Any evidence of acute illness or infection within past 14 days. 3. Planned or elective surgery during the course of the study. 4. Infants born before the 37th week of gestation. 5. Birth weight less than 2.5 kg. 6. Infants with a known or suspected impairment of the immune function, or those receiving immunosuppressive therapy, or having received immunosuppressive therapy within 1 month prior to study entry (including systemic corticosteroids) or those who have received a parenteral immunoglobulin preparation. 7. Any history suggestive of thrombocytopenia or a bleeding disorder. 8. Infants who have received any blood products (within 3 months prior to study entry), cytotoxic agents or radiotherapy. 9. Infants with history of anaphylaxis, or any serious vaccine reaction, or allergy to any vaccine component (e.g. neomycin, gelatine, canine proteins). 10. Infants with any serious chronic disease such as cardiac, autoimmune disease or insulin dependent diabetes or with any condition that in the opinion of the investigator might interfere with the evaluation of the study objectives. 11. Infants whose families are planning to leave the area of the study site before the end of the study period.