Meningococcus B Vaccination Effectiveness against Neisseria gonorrhoeae Infection in People Living with HIV: a Case-control Study.

BACKGROUND: We assessed the vaccination effectiveness (VE) of multicomponent meningococcal serogroup B (4CMenB) vaccine against gonorrhoea among people living with HIV (PLWH) with a previous diagnosis of sexually transmitted infection (STI).

METHODS: Unmatched case-control study on men who have sex with men (MSM) living with HIV, in care at San Raffaele Scientific Institute, Milan, Italy, with gonorrhoea, syphilis, chlamydia or anal HPV between July 2016 (beginning of 4CMenB vaccination) and February 2021 (date of freezing). For the analysis, cases were people with ≥1 gonorrhoea infection since July 2016 and controls were people with ≥1 syphilis, chlamydia, or anal HPV infection since July 2016. Logistic regression was used to provide the estimate of 4CMenB VE against gonorrhoea.

RESULTS: Included PLWH were 1051 (103 cases, 948 controls); 349/1051 (33%) received two doses of 4CMenB vaccination. The median follow-up was 3.8 years (2.1-4.3). The unadjusted estimate for VE against gonorrhoea was 42% (95%CI 6-64; p = 0.027). Logistic regression showed that VE against gonorrhoea remained significant (44%, 95%CI 9-65; p = 0.020) after adjusting for some factors that might have a potential influence on VE or those with significant unbalanced distributions between cases and controls at univariable analysis.

CONCLUSIONS: 4CMenB vaccination is associated with lower risk of gonorrhoea in the setting of MSM living with HIV with a previous STI.