OBJECTIVES: Invasive meningococcal disease (IMD) is a severe infection caused by Neisseria meningitidis, which is associated with high lethality and long-term sequelae. This study aims to evaluate the potential public health impact of implementing adolescent booster strategies with MenACWY and MenC vaccines in Germany, where routine meningococcal immunization is currently limited to MenC in toddlers.

METHODS: We constructed a dynamic transmission model to project meningococcal carriage of five serogroup compartments (AY/B/C/W/Others) across 100 age groups until 2060, with corresponding IMD cases derived using case-carrier ratios. The analysis compared the existing routine MenC toddler immunization to additional MenC or MenACWY boosters at ages 12-14 or 15-17 years, considering vaccine effectiveness against IMD and carriage acquisition in all scenarios.

RESULTS: The model predicted that the introduction of a MenACWY booster could significantly reduce IMD incidence by preventing up to 63 annual IMD cases and a total of 1,466 cases by 2060. This decrease was largely driven by herd effects, which led to a reduction in IMD incidence across all age groups. The protective effect was independent of the vaccination age. Implementation of MenACWY vaccination in adolescents could reduce annual MenACWY IMD mortality by up to 64%. Modelling a scenario with enhanced vaccine protection against carriage could prevent over 2,300 IMD cases until 2060, while scenarios accounting for serogroup replacement would result in fewer prevented IMD cases. In comparison, the introduction of MenC vaccination in adolescents had negligible impact on IMD incidence and mortality.

CONCLUSIONS: Our findings indicate that the introduction of MenACWY vaccination in adolescents in Germany could substantially lower IMD cases and mortality across all age groups. In contrast, adolescent MenC vaccination has minor impact. Given the significant health care resource use associated with IMD, the results suggest economic benefits of implementing a MenACWY booster vaccination.