Immunology and Safety of Menactra® in Children in Saudi Arabia

Inclusion Criteria : * Healthy, as determined by medical history and physical examination. * Aged between 5 to 8 years on the day of inclusion (from 5th birthday to 1 day before 9th birthday inclusive). * For the Booster Group , two doses of a quadrivalent (A, C, Y, W-135) meningococcal polysaccharide vaccine received before age 2 years * For the Control Group , no previous history of any meningococcal vaccination * Informed consent form signed by the parent(s) or other legal representative * Able to provide a vaccination log or has available vaccination record in the Health Center. * Able to attend all scheduled visits and to comply with all trial procedures Exclusion Criteria : * Serious chronic disease (i.e., cardiac, renal, neurologic, metabolic, rheumatologic, psychiatric, etc.) * Known or suspected impairment of immunologic function. * Acute medical illness with or without fever within the last 72 hours or a oral temperature ≥ 37.5°C at the time of inclusion. * Administration of immune globulin or other blood products within the last three months, injected or oral corticosteroids or other immunomodulatory therapy within six weeks of the trial vaccine. Individuals on a tapering dose schedule of oral steroids lasting \< 7 days may be included in the trial provided that they have not received more than one course within the last two weeks prior to enrollment. * Oral or injected antibiotic therapy within the 72 hours prior to vaccination. * Received any vaccine in the 14-day period prior to trial vaccination, or scheduled to receive any vaccination during the 14-day period after trial vaccination. * Previous history of documented invasive meningococcal disease. * For the Control Group, previous history of any meningococcal vaccination. * Systemic hypersensitivity to any of the vaccines components or history of a life-threatening reaction to the trial vaccines or a vaccine containing the same substances. * Participation in another clinical trial in the 4 weeks preceding the trial vaccination * Planned participation in another clinical trial during the present trial period * Any condition, which, in the opinion of the investigator, would pose a health risk to the subject, or interfere with the evaluation of the vaccine. * Personal or family history of Guillain Barré syndrome.