Objective:

To assess the impact of the four-component meningococcal serogroup B vaccine (4CMenB) on gonorrhea and oropharyngeal meningococcal carriage among adolescents in a high-prevalence setting.

Approach:

• Study Design: The study evaluated vaccine effectiveness using linked notification and immunization data and assessed oropharyngeal carriage through swabs collected at baseline and 12 months.
• Population: Included 30,650 adolescents aged 14 to 19 years in Australia's Northern Territory from 2021 to 2023, with 9.6% fully vaccinated and 42.4% identifying as Aboriginal or Torres Strait Islander.

Key Findings:

• Two-dose vaccine effectiveness against gonorrhea was 38.4% (95% CI, 18.6%-53.4%).
• Gonococcal notifications were lower among vaccinated adolescents.
• Overall meningococcal carriage increased from 4% to 6.2%, driven by genogroup B and nongroupable strains.

Interpretation:

The results indicate that the 4CMenB vaccine provides modest protection against gonorrhea in a high-prevalence population.

Limitations:

• Lower-than-anticipated two-dose vaccine uptake.
• Potential residual confounding related to differences in sexually transmitted infection risk and testing patterns.
• Missing data on immunosuppression and 57% of 12-month swab data required imputation.

Conclusion:

Despite limitations, the study demonstrates that 4CMenB offers modest protection against gonorrhea.

Sources:

• Open Forum Infectious Diseases