IMPACT OF DECLINING VACCINATION COVERAGE ON THE RE-EMERGENCE OF MEASLES IN BRAZIL: AN ECOLOGICAL AND DOCUMENTARY ANALYSIS (2015-2025)

Abstract

This article discussed measles as a highly contagious viral disease that, despite being controllable through immunization, re-emerged in Brazil in mid-2019. The study aimed to analyze the association between declining vaccination coverage and the re-emergence of measles in Brazil between 2015 and 2025. It was a quantitative, descriptive, and explanatory study of a documentary and ecological nature, utilizing secondary data from the SI-PNI and SINAN systems (DATASUS). Results showed 39,953 confirmed cases during the period, with an epidemic peak in 2019 (21,754 cases). A shift in the epidemiological epicenter was observed from the Southeast region (São Paulo) during the pre-pandemic period to the North region (Pará) during the post-COVID-19 pandemic period. Statistical analysis demonstrated that the progressive decline in MMR (first dose) vaccine coverage below the World Health Organization (WHO) safety target was the primary driver of the outbreaks. The study concludes that the epidemiological silence observed during the pandemic was a temporary effect of social isolation measures and that, to prevent measles from becoming endemic again, it is urgent to implement public policies that combat vaccine hesitancy and restore herd immunity.