The relationship between vaccination coverage and meningitis cases caused byNeisseria Meningitidis and Streptococcus Pneumoniae from 2012 to 2022 in thelargest cities of the Grande ABC region, SP

Abstract

The cases of meningococcal and pneumococcal meningitis reported between 2012 and 2022 in the seven largest cities of the Grande ABC region in São Paulo were analyzed and compared with vaccination coverage data from the same period. This observational epidemiological study used information from the Notifiable Diseases Information System (SINAN) and the National Immunization Program Information System (SI-PNI), both linked to DATASUS. A total of 7,573 cases of meningitis were recorded, of which 366 (4.83%) were attributed to Neisseria meningitidis and 226 (2.99%) to Streptococcus pneumoniae. The highest incidence rates occurred in São Bernardo do Campo and Santo André, with peaks between 2012 and 2015. In 2018, a significant increase in cases was observed, coinciding with a gradual decline in vaccination coverage, which reached critical levels in 2021, especially in Rio Grande da Serra (32.53%) and Ribeirão Pires (53.84%). Factors such as the COVID-19 pandemic, vaccine hesitancy, and logistical challenges may have contributed to this decline. The data suggest that reduced vaccination coverage influenced the rise in cases, although a direct causal relationship requires further investigation. The persistence of low immunization rates increases the risk of outbreaks in vulnerable populations. It is concluded that maintaining high vaccination levels is essential for controlling meningitis, making it necessary to strengthen public policies, expand access to vaccines, and promote educational campaigns to reverse the decline in immunization and prevent the resurgence of the disease.