Exploring spatiotemporal dynamics and climatic effects on dengue in Amazonas, Peru during 2000-2023

Peru experienced its most severe dengue outbreak on record, with the Amazonas region reporting 3502 dengue cases in 2022. This study aimed to examine the distribution of dengue cases across Amazonas from 2000 to 2023, while exploring the influence of climate factors. Monthly incidence was aggregated into four consecutive six-year blocks to identify incidence trends, and space-time scan statistics identified high and low-risk clusters. Spearman correlations with distributed lags (0 - 2 months) evaluated the association between incidence and climatic data from NASA-POWER, stratified by season. Until 2005, transmission was restricted to Bagua and Utcubamba provinces. A major increase in cases from 2008 to 2011 was recorded in the endemic provinces of Condorcanqui, Bagua, and Utcubamba forming a high-risk cluster in the latter two (LLR = 287.88, RR = 3.79). After a decrease during 2012-2017, incidence resurged creating a Bagua mega-cluster (LLR = 1112.28, RR = 3.20) and expanding to Jazán and Balsas districts, with the latter characterized by lower temperatures compared to endemic areas. Significant correlations were found between climatic variables and incidence. Specifically, minimum temperature significantly influenced dengue dynamics and expansion into Balsas (rho = 0.23, P = 0.03), with a two-month lag during the wet season. These findings underscore the importance of climate monitoring in guiding public health interventions. However, a comprehensive approach that considers environmental and behavioral factors, tailored to the specific conditions of each province, is essential for effective control of future outbreaks.