Meningococcal meningitis is an infection of the membranes that surround the central nervous system; its etiologic agents are multiple, and the mode of transmission varies according to the etiology. One of its main causes is the bacterium Neisseria meningitidis (meningococcus), which is an important cause of death in children and young adults worldwide, including in Brazil. This study aimed to analyze the impact of the introduction of the conjugate meningococcal C vaccine on the incidence, hospitalization, and mortality rates due to meningitis in Brazil, comparing the decade prior to its implementation in the National Immunization Program (2001 to 2010) with the subsequent decade (2011 to 2020), with emphasis on the effects observed in different age groups. This was a quantitative, descriptive ecological study based on information from the Notifiable Diseases Information System, collecting data on the number of notified cases, hospitalizations, and deaths by age group between 2001 and 2020, and data on the resident population available through the TABNET/DATASUS tool for the same period. There was a significant decrease in the incidence of meningitis cases after the introduction of the meningococcal C vaccine in 2010, particularly in age groups under 14 years, the target population of the immunization program. A reduction greater than 50% in incidence was observed among children aged 5 to 14 years between the analyzed periods. The mean incidence across all ages decreased from 14.31 to 8.4 cases per 10,000 inhabitants when comparing the two periods. Mortality also showed a marked reduction in most age groups, especially in children aged 0 to 4 years, whose rate dropped by 72%, from 1.99 to 0.56 deaths per 100,000 inhabitants between the periods. In the 5–9-year age group, mortality fell by 57.46%, from 4.02 to 1.71 deaths per 100,000 inhabitants. In addition, there was a 52.06% decrease in hospitalizations due to meningitis, from 7.47 to 3.58 cases per 10,000 inhabitants between the periods analyzed. The introduction of the meningococcal C vaccine in 2010 contributed to the reduction of incidence, hospitalization, and mortality rates due to meningitis in Brazil, that is, it reduced the risk of infection, disease severity, and death, proving to be an effective control measure against meningitis and highlighting its importance for population health.
Foronda et al. (Sun,) studied this question.