Subjects were previously vaccinated at 11 to 17 months of age with GSK Biologicals' meningococcal vaccine 134612 or with Mencevax™. This extension phase starts 24 months after vaccination and the subjects who were vaccinated in the primary study will be enrolled in this extension phase. No new studies will be enrolled. The subjects will have 4 blood samples taken: at 24, 36, 48 and 60 months after vaccination.
Subjects were previously vaccinated at 11 to 17 years of age. This extension phase starts 24 months after vaccination and the subjects who were vaccinated in the primary study will be enrolled in this extension phase. No new subjects will be enrolled.