Comprehensive spatiotemporal analysis of dengue epidemics in Vietnam reveals key hotspots and transmission dynamics

OBJECTIVES: Dengue fever remains a critical public health challenge worldwide, especially in endemic regions such as Vietnam, where rapid urbanization and climate change exacerbate transmission. Despite frequent outbreaks, the spatiotemporal epidemiology of dengue in Vietnam is poorly characterized. This study aimed to elucidate the epidemic dynamics to inform targeted intervention strategies. METHODS: We analyzed national case and mortality data from 1998 to 2020, employing advanced geospatial analysis tools (R and SatScan) to identify high-risk areas and transmission patterns. RESULTS: Over 23 years, the case fatality rate was consistently low (0.1-0.2%), despite discrepancies between reported dengue virus strains and clinical cases. Key high-risk zones included the Mekong Delta, southern metropolitan areas, south-central Vietnam, and Hanoi, with distinct temporal peaks, primarily between June and November. Notably, southern Vietnam experienced persistent simultaneous outbreaks, whereas the epidemic activity in Hanoi was more localized. CONCLUSIONS: Our findings delineate the critical zones and seasons of dengue transmission in Vietnam, providing essential evidence for optimizing resource allocation and surveillance efforts. These insights are vital for developing preemptive public health interventions in resource-constrained endemic settings.