Subjects who received one dose of Menactra® or Menomune® in study MTA04, MTA12, MTA19 (NCT00777790), or MTA21 (NCT00777257) will be eligible for enrollment in trial this study. All eligible subjects will provide a blood sample at Visit 1, after which their participation in the study will be terminated. An age-matched meningococcal-vaccine naïve control group will be recruited to provide a blood sample for baseline antibody level evaluation.
No vaccine will be administered in this study.