Serogroup A, C, W, and Y meningococcal disease in persons previously vaccinated with a serogroup ACWY meningococcal vaccine - United States, 2014-2018.

BACKGROUND: The Advisory Committee on Immunization Practices (ACIP) recommends routine vaccination with a quadrivalent meningococcal conjugate serogroup A,C,W,Y (MenACWY) vaccine at 11-12 years of age, with a booster dose at 16 years. ACIP also recommends meningococcal vaccination for persons at increased risk of meningococcal disease, including a 2-dose primary series and regular booster doses for persons at increased risk because of underlying medical conditions. U.S. cases of serogroup A, C, W, and Y meningococcal disease in persons previously vaccinated with MenACWY vaccine have not been systematically described since 2008. Characterization of these cases is important to understand potential factors leading to breakthrough disease. METHODS: We analyzed cases of serogroup A,C,W, and Y meningococcal disease reported through the National Notifiable Diseases Surveillance System (NNDSS) from 2014 through 2018. State health departments submitted additional information on risk factors and clinical course. RESULTS: During 2014-2018, 822 cases of serogroup A, C, W, and Y meningococcal disease were reported through NNDSS; 34 (4%) were in patients who previously received ≥ 1 dose of MenACWY vaccine. Twenty-three vaccinated patients were up-to-date on MenACWY vaccine per recommendations, and seven were not up-to-date; four were missing information on the number of doses received. Seventeen cases (50%) occurred > 3 years after the most recent dose. A significantly higher proportion of vaccinated patients were people living with HIV (PLWH) compared to unvaccinated patients. Eight of the 34 vaccinated patients were immunosuppressed, including five PLWH, one taking eculizumab, and two taking other immunosuppressive medications. The case fatality ratio did not differ between vaccinated and unvaccinated patients. CONCLUSIONS: Immunosuppression, incomplete vaccination, and waning immunity likely contributed to breakthrough cases of meningococcal disease among people who received MenACWY vaccine. Continued monitoring of serogroup A, C, W, and Y meningococcal disease in previously vaccinated persons will help inform meningococcal disease prevention efforts.