Epidemiological Profile and Diagnostic Trends of Meningococcal Disease in Brazil Across Pre-, Peri-, and Post-Pandemic Periods

Abstract

Aims: To describe the epidemiological profile and diagnostic trends of meningococcal meningitis with meningococcemia in Brazil before, during, and after the COVID-19 pandemic, with emphasis on diagnostic criteria and regional distribution to assess the impact on these patterns. Study Design:  Ecological study using national surveillance data from the Notifiable Diseases Information System (SINAN). Place and Duration of Study: Brazil, covering 01 January 2015 to 31 May 2024. Methodology: A retrospective, cross-sectional study was conducted using secondary data from the Notifiable Diseases System (SINAN) between 2015 and 2024. Confirmed cases in individuals aged 0–18 years were grouped into three periods: pre-pandemic (2015–2019), peri-pandemic (2020–2022), and post-pandemic (2023–2024). Diagnostic methods were categorized as polymerase chain reaction (PCR), culture, clinical criteria Descriptive analyses, Chi-square tests, and multivariate logistic Information regression were applied. A complete-case analysis was performed after data cleaning to handle missing information. Data were analyzed using R 4.4.2. Pearson’s chi-square test and logistic regression were applied to evaluate associations, with statistical significance set at p < 0.05. Results: A total of 1,186 confirmed cases in individuals aged 0–18 years were analyzed, 917 (77.3%) pre-pandemic, 174 (14.7%) peri-pandemic, and 95 (8.0%) post-pandemic. Diagnostic confirmation by PCR increased from 42.8% before the pandemic to 63.1% afterward, while clinical criteria decreased proportionally. Significant differences were observed between periods for diagnostic method (p<0.001) and case fatality (p=0.038). The odds of diagnosis by PCR were 1.9 times higher in the post-pandemic period compared with the pre-pandemic baseline (95% CI: 1.35–2.68). Conclusion: Despite reduced overall case numbers during the pandemic, PCR-based diagnosis expanded substantially, likely reflecting improved laboratory capacity and surveillance integration post-COVID-19. The findings highlight both progress and persistent disparities in meningococcal disease reporting across Brazilian regions.