Temperature-based Dengue Outbreaks Modelling with Exogenous Variables

Abstract

Dengue fever is an endemic disease, present in tropical and subtropical regions, transmitted by the Aedes Aegypti mosquito vector. It has recently appeared in non-tropical regions with dry weather. This represents a setback for advanced temperature-based reference models, since mosquitos reproductive cycle does not necessarily match with the outbreaks. This situation indicates that other variables are also involved in epidemic outbreaks. In this work we propose to include a component that capture this process, whether entomological, environmental or related to population mobility, and include it to the reference model by adding a Gaussian function to the formulation of humans (β h ) and vectors (βv) transmission rate. The parameters to be adjusted for this function were evaluated by a probabilistic model selection experiment. The parameters for this function are u, σ and k. The results indicate that, our model outperforms the reference model, and that additional information about outbreaks can be obtained from the new parameters. .

SIR-SI model with a Gaussian transmission rate: Understanding the dynamics of dengue outbreaks in Lima, Peru

“…To capture this phenomenon, we considered the effects of weather on the transmission rate by replacing the constants x 1 and x 2 with a time-dependent variable b ex 2 R resulting from a Gaussian function. The Gaussian function is defined as [14] b ex ≔k e À ðx À uÞ 2 2s 2 ; ð11Þ…”

“…There was a strong correlation between the temperature and bb v , but β ex was needed to adjust β hv (similar results were obtained for β vh ). The importance of considering the modulation is relevant because several studies have reported that the climate-based variables determine the prediction and fitting of the SIR-SI model [14,18,24]. It is important to note that the climate of Lima is characterized by low levels of rainfall and variable temperature according to region owing to the effects of the ocean and the Andes Mountains.…”

“…Several compartmental models have been developed to explain the spread of dengue, from simple models such as susceptible-infected-recovered (SIR) to more complex models such as susceptible-exposed-infected-recovered (SEIR) and human susceptible-infected-recovered and vector susceptible-infected (SIR-SI) [11,[13][14][15]. These epidemiological models are important for explaining the transmission dynamics of dengue and for developing control measures [16,17].…”