Snape and colleagues report that a fifth or booster dose of the multicomponent serogroup B meningococcal (4MenB) B vaccine given to 40- to 44-month-old children previously 4MenB immunized at 2, 4, 6 and 12 months of age resulted in a good anamnestic response compared to vaccine-naïve controls. The U.K., where this study was conducted, recently considered and rejected a recommendation for routine use of 4MenB in infants based on the limited vaccine preventable disease burden and the unfavorable cost-effectiveness.
The study by Snape et al provides evidence that like other meningococcal vaccines, bactericidal antibodies, a correlate of protection, wane among young children 2-3 years after the primary series and first booster, but elicit a robust immune response to the second booster or fifth dose. However, hSBA activity, a correlate of protection for capsular polysaccharide-protein conjugate meningococcal vaccines, is based on antibodies binding to a single capsular epitope.
For 4MenB vaccine, 4 distinct protein components that have considerable interstrain variation make the “protection” assumption far less certain. Furthermore, it is likely that herd immunity will be required for 4MenB to be protective in any given target population, and it is not known whether it diminishes nasopharyngeal carriage among unvaccinated in a manner similar to Haemophilus influenzae and Streptococcus pneumoniae conjugate vaccines. Until the burden of meningococcal serogroup B disease is such to justify routine use of 4MenB in infants and young children, the potential effectiveness of this vaccine will remain uncertain.
Carol J. Baker, MD
Professor, Molecular Virology & Microbiology
Baylor College of Medicine
Disclosures: Baker reported being a consultant for Novartis Vaccines and Diagnostic.