One Year Antibody Persistence After a Fourth Dose Boost or Two Catch-Up Doses of Novartis Meningococcal B Recombinant Vaccine Administered Starting From 12 Months of Age and Response to a Third Dose Boost or Two Catch-Up Doses Starting at 24 Months of Age

Inclusion Criteria: * Healthy male and female children, 23 to 27 months of age (naïve children) * Available for all the visits scheduled in the study; * For whom parent(s)/legal guardian(s) have given written informed consent according to local regulations after the nature of the study has been explained; * Available for all the visits scheduled in the study; * In good health as determined by medical history, physical examination, clinical judgment of the investigator. * Healthy children who participated in the immunogenicity part of V72P13E1 and have received their last vaccination 12 months (-30/+60 days) before enrolment in V72P13E2; * Who received all vaccinations with rMenB+OMV NZ in V72P13 and V72P13E1 according to the protocols; * Who provided at least the blood sample one month after their fourth dose of rMenB+OMV NZ (groups B246\_12M12/B246\_12M13) or after their second dose of rMenB+OMV NZ (groups B13\_15\_27/B12\_14\_26) in V72P13E1 according to the protocol; * For whom parent(s)/legal guardian(s) had given written informed consent after the nature of the study has been explained; * In good health as determined by medical history, physical examination, clinical judgment of the investigator. Exclusion Criteria: * Subjects whose parent(s)/legal guardian(s) were unwilling or unable to give written informed consent to participate in the study; * History of any meningococcal B vaccine administration; * Previous ascertained or suspected disease caused by N. meningitid…