Persistence of Antibodies After Meningococcal Vaccine PF-06866681 in Healthy Children

Inclusion Criteria: All subjects must satisfy ALL the following criteria at study entry: * Subjects' parent(s)/Legally Acceptable Representative(s) \[LAR(s)\] who, in the opinion of the investigator, can and will comply with the requirements of the protocol. * A male or female who has received primary and booster vaccination with the MenACWY-TT or Meningitec vaccines in studies MENACWY-TT-039 (109670) and MENACWY-TT-048 EXT: 039 Y2, 3, 4, 5 (112036), respectively. * Written informed consent obtained from the parent(s)/LAR(s) of the subject. * Healthy subjects as established by medical history and clinical examination before entering into the study. Exclusion Criteria: The following criteria should be checked at the time of study entry. If ANY exclusion criterion applies, the subject must not be included in the study: * Child in care. * History of meningococcal disease. * Administration of a meningococcal polysaccharide or a meningococcal polysaccharide conjugate vaccine outside of studies MENACWY-TT-039 (109670) and MENACWY-TT-048 EXT: 039 Y2, 3, 4, 5 (112036). * Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination. * Bleeding disorders, such as thrombocytopenia, or subjects on anti-coagulant therapy.