Analysis of Reported Cases of Meningococcal Disease in Brazil and the Impacts of Vaccination in the Last 15 Years

Abstract

Introduction: Meningococcal meningitis is the inflammatory process of the subarachnoid space and the leptomeningeal membranes of infectious etiology, whose etiological agent is the bacterium Neisseria meningitidis (meningococcus). Objective: To analyze the notifications of cases of meningococcal meningitis in Brazil over the last 15 years, focusing on the impacts of vaccination and trends in incidence, as well as evaluating the effectiveness of public health strategies in controlling the disease. Methodology: This is a descriptive epidemiological survey based on data from the Notification Disease Information System (SINAN) between 2009 and 2023. Information was collected on cases of meningococcal meningitis, including demographic variables, mortality rates, diagnosis, and serogroups. Variables were organized, summarized, described and compared using Descriptive Statistics methods. The analysis included data on notifications, deaths, and vaccination coverage, complemented by a literature review. Results: Between 2009 and 2023, Brazil recorded 22,601 cases of meningococcal meningitis. Of these, 15,767 recovered and 4,864 resulted in deaths from meningitis. The Southeast region was the most affected, with 14,333 cases, followed by the Northeast (n=3,593), South (n=2,501), Midwest (n=1,184), and North (n=990). In terms of sex, 56,28% (n=12.722) of cases were in men. Serogroup C was responsible for the majority of cases, accounting for 33.99% (n=7,682) of the total, followed by serogroup B with 10.95% (n=2,474). Vaccination against meningococcal C showed coverage above 90% between 2010 and 2016 but fell to 72.17% in 2021. Conclusion: There was a decline in reported cases and deaths over the years, however, an increase was noticed in 2022, following the COVID-19 pandemic. The decrease in vaccination coverage could also be associated with the rise in cases and deaths in 2022 and 2023. Serogroup C showed the highest incidence, but serogroup B also exhibited significant variations over the analyzed period.