O-59 The effect of climate variables on the incidence of Dengue in Brazil
Author(s):
G Nightingale, A Seaton, S Villejo, N Oliveira de Moura, L Brondi, C Henriques, E Rydzewska-Fazekas, E Giorgi
Year of Presentation:
2025
Objective: This study aimed to evaluate the effect of climate
variables (e.g., temperature and rainfall) on Dengue morbidity and to describe the spatiotemporal trends of Dengue
fever (DF) incidence in the presence of other explanatory
variables, such as the social deprivation Index in Brazil.
Methods: This secondary analysis combined Dengue fever surveillance data (2010-2019) with climate variables and national population data, including a socio-economic index and Brazilian Index of Deprivation. The number of monthly probable cases of Dengue Fever was modelled based on a spatiotemporal model using Poisson regression with a log link where a population offset was applied, which included a Brazilian index of deprivation as a covariate.
Results: The models used suggested an association between temperature and Dengue incidence and this relationship was modified by social deprivation. The effect of rainfall was less clear. The monthly incidence of DF varied seasonally. The effect of mean maximum daily temperature on DF incidence was stronger for urban areas with higher index of deprivation.
Conclusion: The importance of climate change as a driver of higher incidence of arboviral diseases such as Dengue fever in South America, has been highlighted by several studies in the last decade. The compounded effect of social determinants of health in the context of climate change has, on the contrary, received less attention. Understanding the spatiotemporal patterns of DF transmission in Brazil can provide information for effective public health action. Importantly these can inform policies in the Caribbean as well.