Spatiotemporal evolution of dengue outbreaks in Brazil.

Abstract

Dengue is a mosquito-borne febrile disease infecting millions of people worldwide. Identification of high-risk areas will allow public health services to concentrate their efforts in areas where outbreaks are most likely to occur. The present study focuses on describing the spatiotemporal evolution of dengue outbreaks in Brazil from 2000 to 2018. To assess the pattern behaviour and spatiotemporal trend of dengue outbreaks, the non-parametric kernel estimator method and the Mann-Kendall test, respectively, were used. Bivariate global Moran's I statistic was used to test the spatial correlation between dengue outbreaks, temperature, precipitation and population data. Our results revealed that the transmission cycles of dengue outbreaks vary in different spatiotemporal scenarios, with intermittent periods of outbreaks. In the period of study, outbreak clusters were primarily concentrated in the Northeast region and the transmission of dengue extended throughout Brazil until 2018. The probability of occurrence of dengue outbreaks was higher in high temperatures. Further, these space-time fluctuations in the number of outbreaks in the different regions were probably related to the high mobility between the populations of these regions, circulating serotypes and susceptible populations. The distribution of dengue outbreaks is not random; it can be modified by socioeconomic and climatic moving boundaries.