Spatiotemporal dynamics of waterborne and foodborne disease outbreaks in Brazil: regional inequality analysis and risk area mapping to inform public health strategies

BACKGROUND: Waterborne and foodborne diseases (WFD) represent a relevant public health challenge, especially in countries marked by social and sanitary vulnerabilities. This study analysed the spatiotemporal dynamics of WFD outbreaks in the country to support surveillance and control strategies. METHODS: This population-based ecological study uses data from the Brazilian Ministry of Health on WFD outbreaks reported between 2007 and 2023. Spatial patterns were analysed via the local empirical Bayesian method, Moran’s I, and local indicators of spatial association (LISA). Spatiotemporal patterns were assessed through emerging hotspot analysis and space-time scan statistics. Seasonality was evaluated via the Kruskal–Wallis test, and temporal trends were analysed via Prais–Winsten regression. RESULTS: A total of 11,809 WFD outbreaks were reported in Brazil, with an average incidence of 34.2 outbreaks per 10 million inhabitants. A heterogeneous and scattered spatial distribution was observed, with high-incidence clusters concentrated in the South and a low incidence in the Northeast. Fernando de Noronha Island (PE) was the only location identified as part of the most likely spatiotemporal cluster. Seventy municipalities were classified as persistent hotspot areas. Overall, the trend was stationary, with a decrease in outbreaks involving identified pathogens, particularly Salmonella spp., Staphylococcus spp., Bacillus cereus, and Clostridium spp., and an increase in outbreaks caused by norovirus. CONCLUSIONS: The findings highlight challenges for outbreak surveillance and control, including possible laboratory limitations, underreporting, and regional disparities in detection capacity, underscoring the need for coordinated actions to strengthen notification and response systems. Strengthening the active surveillance and training of health teams is essential to mitigate impacts and enhance response capacity. Regional studies that consider environmental, behavioural, and socioeconomic factors, along with analyses of sanitation infrastructure and primary healthcare coverage, can support more effective prevention and control strategies.