The everchanging epidemiology of meningococcal disease worldwide and the potential for prevention through vaccination.

Neisseria meningitidis is a major cause of bacterial meningitis and septicaemia worldwide and is associated with high case fatality rates and serious life-long complications among survivors. Twelve serogroups are recognised, of which six (A, B, C, W, X and Y) are responsible for nearly all cases of invasive meningococcal disease (IMD). The incidence of IMD and responsible serogroups vary widely both geographically and over time. For the first time, effective vaccines against all these serogroups are available or nearing licensure. Over the past two decades, IMD incidence has been declining across most parts of the world through a combination of successful meningococcal immunisation programmes and secular trends. The introduction of meningococcal C conjugate vaccines in the early 2000s was associated with rapid declines in meningococcal C disease, whilst implementation of a meningococcal A conjugate vaccine across the African meningitis belt led to near-elimination of meningococcal A disease. Consequently, other serogroups have become more important causes of IMD. In particular, the emergence of a hypervirulent meningococcal group W clone has led many countries to shift from monovalent meningococcal C to quadrivalent ACWY conjugate vaccines in their national immunisation programmes. Additionally, the recent licensure of two protein-based, broad-spectrum meningococcal B vaccines finally provides protection against the most common group responsible for childhood IMD across Europe and Australia. This review describes global IMD epidemiology across each continent and trends over time, the serogroups responsible for IMD, the impact of meningococcal immunisation programmes and future needs to eliminate this devastating disease

Epidemiological burden of meningococcal disease in Brazil: A systematic literature review and database analysis

Objectives: The aim of this study was to evaluate the epidemiological profile of invasive meningococcal disease (IMD) in Brazil, the first Latin American country to introduce the group C meningococcal conjugate vaccine (included in the vaccination schedule in 2010). Methods: A systematic review was conducted, covering the years 2005–2017, to identify epidemiological information on IMD and Neisseria meningitidis carriers in Brazil. Documents from the Brazilian Ministry of Health and two public databases were analyzed to determine annual incidence rates, absolute numbers of diagnosed cases, serogroups identified, the relative distribution of cases per serogroup, and the case fatality rate (CFR). Results: Sixteen studies were selected. The incidence rate ranged from 0.88 to 5.3 cases per 100 000 inhabitants per year. According to secondary data, the annual incidence of IMD in 2015 was highest in males <1 year old (7.1/100 000). The number of diagnosed cases declined significantly over the years. In the literature, IMD showed a CFR from 20.0% to 50.0%, and a higher CFR for serogroup W (17.8%). Secondary data showed an absolute reduction in meningitis-attributable deaths between 2007 and 2015; however, the CFR remained stable (11.1% in 2007 and 8.4% in 2015). In 2015, serogroup W showed the highest CFR (24.1%), followed by serogroups C (19.2%), B (17.7%), and Y (14.3%). Conclusions: Despite a reduction in cases, the CFR remained stable and similar in the different age groups, even for disease caused by different serogroups. The highest CFR was found to be associated with serogroup W. Keywords: Meningitis, Meningococcal, Brazil, Epidemiology, Serogroup, Neisseria meningitidis, Meningococcal vaccine

The Impact of Social Determinants of Health on Meningococcal Vaccination Awareness, Delivery, and Coverage in Adolescents and Young Adults in the United States: A Systematic Review

Vaccines remain a fundamental intervention for preventing illness and death. In the United States, suboptimal vaccine uptake in adolescents and young adults has been observed for meningococcal conjugate (MenACWY) and serogroup B meningococcal (MenB) vaccines, particularly among marginalized communities, despite current recommendations by the Advisory Committee on Immunization Practices. A systematic literature search was conducted in the MEDLINE and MEDLINE In-Process, Embase, Cochrane, PsychInfo, and CINAHL databases to identify both drivers of, and barriers to, MenACWY and MenB vaccine uptake in adolescents and young adults. A total of 34 of 46 eligible studies that presented outcomes stratified by race/ethnicity, geography, and socioeconomic status were selected for review. Results showed MenACWY and MenB vaccination coverage in adolescents and young adults is impacted by racial/ethnic, socioeconomic, and geographic disparities. Gaps also exist in insurance for, or access to, these vaccines in adolescents and young adults. Moreover, there was variability in the understanding and implementation of the shared decision-making recommendations for the MenB vaccine. Disease awareness campaigns, increased clarity in accessing all meningococcal vaccines, and further research on the relationships between measures of marginalization and its impact on vaccine coverage in adolescents and young adults are needed to reduce the incidence of severe infections