Impact of Meningococcal B (4CMenB) Vaccine on Pharyngeal Neisseria meningitidis Carriage Density and Persistence in Adolescents

Mark McMillan, Luke Walters, Thomas Sullivan, Lex E.X. Leong, Mark Turra, Andrew Lawrence, Ann P. Koehler, Adam Finn, Ross M. Andrews, Helen S. Marshall

    Research output: Contribution to journalArticlepeer-review

    17 Citations (Scopus)

    Abstract

    Background: Higher density of Neisseria meningitidis carriage may be associated with transmission of the meningococcus. Our aim was to establish the impact of meningococcal B (4CMenB) vaccine on N. meningitidis carriage density. Methods: We compared 4CMenB vaccine to control among 913 South Australian students aged approximately 15-18 years in a cluster randomized trial who had N. meningitidis carriage at 12 months. Oropharyngeal swabs were collected at baseline and 12 months later to detect N. meningitidis carriage. Colony-forming units per milliliter (CFU/mL) were estimated by generating a standard curve that plotted quantitative polymerase chain reaction cycle threshold values against log-normalized CFU. Results: Among the 913 students with N. meningitidis carriage at 12 months, there was no difference in mean carriage density between the vaccinated (n = 434; 3.80 log CFU/mL [standard deviation {SD}, 1.29]) and control group (n = 479; 3.73 log CFU/mL [SD, 1.30]; P = .51). Higher N. meningitidis carriage density at baseline was associated with an increase in the odds of persistent carriage at 12 months (n = 504; odds ratio [OR] per 1.0 log CFU/mL increase in density, 1.36 [95% confidence interval {CI}, 1.17-1.58]; P < .001). Students with baseline carriage who were vaccinated had decreased persistent N. meningitidis carriage at 12 months compared to unvaccinated students (81/260 [31%] vs 105/244 [43%]; OR, 0.60 [95% CI,. 40-.90]; P = .01). Conclusions: 4CMenB vaccine did not reduce carriage density of N. meningitidis 12 months postvaccination, despite increased carriage clearance. Higher carriage density is likely to enable transmission through prolonged periods of population exposure. Clinical Trials Registration: NCT03089086.

    Original languageEnglish
    Pages (from-to)E99-E106
    JournalClinical Infectious Diseases
    Volume73
    Issue number1
    DOIs
    Publication statusPublished or Issued - 1 Jul 2021

    Keywords

    • carriage
    • density
    • public health
    • risk factors
    • vaccines

    ASJC Scopus subject areas

    • Microbiology (medical)
    • Infectious Diseases

    Cite this