Antibody Persistence, and Safety and Tolerability of a Booster Dose of the Meningococcal B Vaccine After the Completion of the Vaccination Course in Study V72_28

Inclusion Criteria

For naïve subjects newly enrolled:

• Healthy infants and children according to the following age groups:
• Healthy subjects from 35 to 47 months of age, (only applicable to group K) (The age window is defined as the first day the subject turns 35 months of age up to the day before the subject turns 48 months of age),
• Healthy subjects 4 to 7 years of age (only applicable to group L) (The age window is defined as the first day the subject turns 4 years of age up to the day before the subject turns 8 years of age).
• Healthy subjects 8 to 12 years of age (only applicable to group M) (The age window is defined as the first day the subject turns 8 years of age up to the day before the subject turns 13 years of age).
• for whom a parent/legal guardian has given written informed consent after the nature of the study has been explained;
• for whom a parent/legal guardian confirmed availability for the visit scheduled in the study;
• in good health as determined by medical history, physical examination, clinical judgment of the investigator.

For Subjects who participated in the V72\_28 study (Follow-on Subjects):

• for whom a parent/legal guardian has given written informed consent after the nature of the study has been explained;
• for whom a parent/legal guardian confirmed availability for the visit scheduled in the study;
• in good health as determined by medical history, physical examination, clinical judgment of the investigator
• who have completed the vaccination course in the V72\_28 study and have received their last vaccination 24 to 36 months before enrollment in V72\_28E1

Exclusion Criteria

For naïve subjects newly enrolled:

• History of any serogroup B meningococcal vaccine administration;
• Previous known or suspected disease caused by N. meningitidis;
• Household contact with and/or intimate exposure to an individual with laboratory confirmed N. meningitidis infection or colonization;
• History of severe allergic reaction after previous vaccinations or hypersensitivity to any component of the vaccine;
• Pregnancy or nursing (breastfeeding) mothers;
• Females of childbearing age who have not used or do not plan to use acceptable birth control measures, for the duration of the study. Oral, injected or implanted hormonal contraceptive, barrier methods (condom or diaphragm with spermicide), intrauterine device, surgical sterilization, transdermal delivery, congenital sterility or sexual abstinence are considered acceptable forms of birth control. If sexually active the subject must have been using one of the accepted birth control methods at least two months prior to study entry;
• Known or suspected autoimmune disease or impairment/alteration of the immune system resulting from (for example):
• Receipt of any chronic immunosuppressive therapy
• Receipt of any chronic immunostimulants
• Immune deficiency disorder, or known HIV infection
• History of seizure, any progressive neurological disease or Guillain Barré Syndrome (exception: one self-limited febrile seizure is acceptable).
• Known bleeding diathesis or any condition that may be associated with a prolonged bleeding time.
• Subject's parent(s) or legal guardian(s) are not able to comprehend and to follow all required study procedures for the whole period of the study.
• Intent to participate in another clinical study during this study.
• Family members and household members of study staff;
• History or any illness/condition which, in the opinion of the investigator, might interfere with the evaluation of the study objectives or pose additional risk to the subjects due to participation in the study.
• Any significant chronic infection.
• Any serious chronic or progressive disease according to judgment of the investigator (e.g. neoplasm, insulin dependent diabetes, cardiac, renal or hepatic disease).

For Subjects who participated in the V72\_28 study (Follow-on Subjects):

Exclusion criteria are the same as