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Epidemiology of Serogroup B Meningococcal Outbreaks and Interim Guidelines for the Use of an Unlicensed Serogroup B Vaccine Under a CDC-Sponsored IND for the Control of Outbreaks in Organizational Settings Open Access

Background. In 2013, two universities in the United States responded to outbreaks of serogroup B meningococcal (MenB) disease with mass vaccination campaigns using an unlicensed MenB vaccine under a CDC-sponsored Investigational New Drug (IND) program. An evaluation of the current epidemiology of meningococcal disease outbreaks and development of guidelines for use of an unlicensed MenB vaccine under a CDC-sponsored IND are important to guide decision-making until a licensed MenB vaccine is available in the US.

Methods. A retrospective review of meningococcal cases reported since January 1, 2009, was conducted by state health departments and CDC to identify clusters of meningococcal disease. A cluster was defined as 2 or more cases of the same serogroup in an organization in <3 months (organization-based) or a two-fold increase in disease rates in a community (community-based). A Meningococcal Outbreak Work Group was convened to evaluate the epidemiological data and literature, consider options for updating the current meningococcal disease outbreak guidelines, and develop guidance for the use of meningococcal vaccines in an outbreak setting.

Results. Preliminary review of the epidemiologic data revealed 48 meningococcal clusters identified from 14 states: 14 organization-based and 34 community-based. The majority of organization-based clusters were due to serogroup B disease (9, 64%), and five of them were associated with universities. The median number of cases in an organization-based MenB cluster was 2 (range: 2-9) and cases had a median age of 19 years (range: 1-50). The median number of days from onset of the first to last case in organization-based MenB outbreaks was 6.5 days (range: 2-616). The Work Group developed interim guidelines for the use of an unlicensed serogroup B vaccine under a CDC-sponsored IND in response to organization-based MenB outbreaks.

Conclusion. With high coverage of quadrivalent meningococcal vaccine among adolescents, serogroup B is now the most common cause of meningococcal outbreaks in organization-based settings. Interim guidance for the evaluation and control of MenB outbreaks will assist in the decision for mass vaccination, clarify the process for obtaining the vaccine, and improve timeliness of implementation of a vaccination campaign.

Disclosures. All authors: No reported disclosures.

Author notes