Study of Antibody Responses After a Dose of Tetravalent Meningococcal Diphtheria Conjugate Vaccine in Children

Inclusion Criteria : * Participant is healthy, as determined by medical history and physical examination. * Participant is 2 years to \< 5 years of age at the time of vaccination. * At least one year from primary vaccination with a monovalent meningococcal C conjugate vaccine has elapsed. * Parent/Guardian has signed an Ethics Committee-approved informed consent form. A culturally appropriate translation will be used for non-English speaking participants where required. Exclusion Criteria : * Serious chronic disease (i.e. cardiac, renal, neurologic, metabolic, rheumatologic, etc.) * Known or suspected impairment of immunologic function * Acute medical illness with or without fever within the last 72 hours or an axillary temperature ≥ 37.5ºC at the time of inclusion * History of documented invasive meningococcal disease * Administration of immune globulin, other blood products within the last three months, injected or oral corticosteroids or other immunomodulatory therapy within six weeks of the study vaccine. Individuals on a tapering dose schedule of oral steroids lasting \< 7 days may be included in the trial as long as they have not received more than one course within the last two weeks prior to enrolment * Antibiotic therapy within the 72 hours prior to vaccination or 72 hours prior to drawing any blood sample * Received any vaccine in the 28-day period prior to enrolment, or scheduled to receive any vaccine during enrolment in the trial * Received a meningococcal C conjugate vaccine within one year prior to enrolment * Suspected or known hypersensitivity to any of the vaccine components * Unavailable for the entire study period or unable to attend the scheduled visits or to comply with the study procedures * Enrolled in another clinical trial * Any condition, which, in the opinion of the investigator, would pose a health risk to the participant or interfere with the evaluation of the vaccine.