In addition, this study will characterize the antibody response to a fifth dose boost in all children who received a three-dose primary series of rMenB+OMV NZ at 2, 3, 4 months of age (in parent study V72P12, NCT00721396), and only in a subset of children who received a three-dose primary series of rMenB+OMV NZ at 2, 4, 6 months of age (in parent study V72P12). Antibody response will also be characterized to a third dose boost of rMenB+OMV NZ administered at approximately 4 years of age in all children who received a two catch-up doses of rMenB+OMV NZ as toddlers in study V72P12E1.