Meningococcal carriage in adolescents in the United Kingdom to inform timing of an adolescent vaccination strategy.

OBJECTIVES: Recent development of serogroup B meningococcal (MenB) vaccines highlights the importance of pharyngeal carriage data, particularly in adolescents and young adults, to inform implementation strategies. We describe current UK carriage prevalence in this high risk population and compare methods of carriage detection. METHODS: In this multisite study, pharyngeal swabs were collected on 3-4 occasions over 6-12 months, from 1040 school and university students, aged 10-25 years. Meningococcal carriage was detected by standard culture combined with seroagglutination or PCR of cultured isolates, or by direct PCR from swab. The factor H binding protein (fHBP) variants present in meningococcal isolates were determined. RESULTS: Meningococcal serogroups B and Y were most common, with carriage up to 6.5% and 5.5% respectively, increasing throughout adolescence. Identification by seroagglutination was often unreliable, and the sensitivity of direct PCR detection was 66% compared to culture combined with PCR. Of MenB isolates, 89.1% had subfamily A variants of fHBP. The acquisition rate of MenB carriage was estimated at 2.8 per 1000 person-months. CONCLUSIONS: If vaccination is to precede the adolescent rise in MenB carriage, these data suggest it should take place in early adolescence. Studies assessing vaccine impact should use molecular methods to detect carriage.

Persistence of bactericidal antibodies following early infant vaccination with a serogroup B meningococcal vaccine and immunogenicity of a preschool booster dose.

BACKGROUND: The multicomponent serogroup B meningococcal (4CMenB) vaccine was recently licensed for use in Europe. There are currently no data on the persistence of bactericidal antibodies induced by use of this vaccine in infants. Our objective was to evaluate serogroup B-specific bactericidal antibodies in children aged 40-44 months previously vaccinated at 2, 4, 6 and 12 months of age. METHODS: Participants given 4 doses of 4CMenB as infants received a fifth dose of the vaccine at 40-44 months of age. Age-matched participants who were MenB vaccine-naive received 4CMenB and formed the control group. We evaluated human complement serum bactericidal activity (hSBA) titres at baseline and 1 month after each dose of 4CMenB. RESULTS: Before a booster dose at enrolment, 41%-76% of 17 participants previously vaccinated with 4CMenB in infancy had hSBA titres of 4 or greater against 4 reference strains. Before vaccination in the control group (n = 40) these proportions were similar for strains 44/76-SL (63%) and M10713 (68%) but low for strains NZ98/254 (0%) and 5/99 (3%). A booster dose in the 4CMenB-primed participants generated greater increases in hSBA titres than in controls. INTERPRETATION: As has been observed with other meningococcal vaccines, bactericidal antibodies waned after vaccination with 4CMenB administered according to an approved infant vaccination schedule of 2, 4, 6 and 12 months of age, but there was an anamnestic response to a booster dose at 40-44 months of age. If 4CMenB were introduced into routine vaccination schedules, assessment of the need for a booster dose would require data on the impact of these declining titres on vaccine effectiveness. ClinicalTrials.gov, no. NCT01027351.

Bactericidal antibody persistence 2 years after immunization with 2 investigational serogroup B meningococcal vaccines at 6, 8 and 12 months and immunogenicity of preschool booster doses: a follow-on study to a randomized clinical trial.

BACKGROUND: In a previous study, 60 infants receiving an investigational serogroup B meningococcal vaccine containing recombinant meningococcal proteins alone (rMenB) or combined with an outer membrane vesicle from Neisseria meningitidis (4CMenB) at 6, 8 and 12 months of age produced serum bactericidal antibodies (SBAs) against meningococcal strains expressing vaccine antigens. We studied persistence of this response and the response to a booster dose of vaccine. METHODS: In this extension study, SBA titers were evaluated before and after a booster dose of rMenB or 4CMenB at 40 months of age. MenB vaccine naïve age-matched children served as a control group. RESULTS: Before the booster doses, the proportions of 4CMenB recipients with SBA titers ≥1:4 were 36% (n = 14, 95% confidence interval: 13-65%) for strain 44/76-SL, 100% (77-100%) for 5/99, 14% (2-43%) for NZ98/254 and 79% (49-95%) for M10713. These percentages were 14% to 29% for rMenB recipients (n = 14), except for 5/99 (93%, 66-100%). For controls (n = 40), these proportions were ≤3% for all strains except M10713 (53%, 36-68%). One month after the boosters, ≥93% of 4CMenB recipients had SBA titers ≥1:4 for all 4 strains. For controls receiving their first dose of 4CMenB, 23% (11-39%) had SBA titers ≥1:4 for NZ98/254, compared with 62% to 87% for the remaining strains. CONCLUSIONS: Bactericidal antibodies wane after infant immunization with rMenB or 4CMenB, but there is an anamnestic response to a booster dose. Booster doses of 4CMenB may be required to maintain immune protection through childhood and adolescence.

Immunogenicity and tolerability of recombinant serogroup B meningococcal vaccine administered with or without routine infant vaccinations according to different immunization schedules: a randomized controlled trial.

CONTEXT: In the absence of an effective vaccine, serogroup B Neisseria meningitidis (MenB) remains a major cause of invasive disease in early childhood in developed countries. OBJECTIVE: To determine the immunogenicity and reactogenicity of a multicomponent MenB vaccine (4CMenB) and routine infant vaccines when given either concomitantly or separately. DESIGN, SETTING, AND PARTICIPANTS: Phase 2b, multicenter, open-label, parallel-group, randomized controlled study of 1885 infants enrolled at age 2 months from August 2008 to July 2010 in Europe. INTERVENTION: Participants were randomized 2:2:1:1 to receive (1) 4CMenB at 2, 4, and 6 months with routine vaccines (7-valent pneumococcal and combined diphtheria, tetanus, acellular pertussis, inactivated polio, hepatitis B, Haemophilus influenzae type b vaccines); (2) 4CMenB at 2, 4, and 6 months and routine vaccines at 3, 5, and 7 months; (3) 4CMenB with routine vaccines at 2, 3, and 4 months; or (4) routine vaccines alone at 2, 3, and 4 months. MAIN OUTCOME MEASURES: Percentage of participants with human complement serum bactericidal activity (hSBA) titer of 1:5 or greater against 3 MenB strains specific for vaccine antigens (NZ98/254, 44/76-SL, and 5/99). RESULTS: After three 4CMenB vaccinations, 99% or more of infants developed hSBA titers of 1:5 or greater against strains 44/76-SL and 5/99. For NZ98/254, this proportion was 79% (95% CI, 75.2%-82.4%) for vaccination at 2, 4, and 6 months with routine vaccines, 86.1% (95% CI, 82.9%-89.0%) for vaccination at 2, 4, and 6 months without routine vaccines, and 81.7% (95% CI, 76.6%-86.2%) for vaccination at 2, 3, and 4 months with routine vaccines. Responses to routine vaccines given with 4CMenB were noninferior to routine vaccines alone for all antigens, except for the responses to pertactin and serotype 6B pneumococcal polysaccharide. Fever was seen following 26% (158/602) to 41% (247/607) of 4CMenB doses when administered alone, compared with 23% (69/304) to 36% (109/306) after routine vaccines given alone and 51% (306/605) to 61% (380/624) after 4CMenB and routine vaccines administered together. CONCLUSION: A 4CMenB vaccine is immunogenic against reference strains when administered with routine vaccines at 2, 4, and 6 or at 2, 3, and 4 months of age, producing minimal interference with the response to routine infant vaccinations. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00721396.