Spatiotemporal dynamics of dengue spread in Rio de Janeiro during epidemic periods.

Dengue, the most prevalent urban arbovirus in the world, has triggered recurrent epidemics in Rio de Janeiro, Brazil, since the 1980s. This study aimed to describe the spatial-temporal patterns of dengue spread during the epidemic years of 2002, 2008, 2011, 2012, 2013, and 2024 in Rio de Janeiro. This is an ecological study using secondary data on notified confirmed dengue cases aggregated by neighbourhood. The incidence rates were estimated via the local empirical Bayes method. The local spatial autocorrelation indicators assessed incidence clusters, and the monthly geographic trajectory was outlined for each year. The results revealed changes in the spatial distribution of dengue over time, with clusters of high incidences predominating in the northern and central neighbourhoods in 2002 and 2008, and in the western zone in 2011, 2012, and 2013. In 2024, the distribution was predominant throughout the city, with emphasis in the central and western zones. The monthly geographic centre of dengue cases shifted from the west to the north during the peak of the epidemic. These results highlight the heterogeneous nature of dengue transmission in Rio de Janeiro. The incorporation of spatial and temporal analyses in epidemiological studies can enhance targeted and localized dengue control strategies.