Modeling the impact of climate change transmission dynamics in Ethiopia

Lemma, Abraham Girma; Bekele, Bewketu Teshale; Tilahun, Getachew Teshome

doi:10.22075/ijnaa.2025.37143.5420

Modeling the impact of climate change transmission dynamics in Ethiopia

Articles in Press

Document Type : Research Paper

Authors

Abraham Girma Lemma ¹

Bewketu Teshale Bekele ²

Getachew Teshome Tilahun ³

¹ Department of Mathematics, Bule Hora University, Bule Hore, Ethiopia

² Department of Mathematics, Debremarkos University, Debremarkos, Ethiopia

³ Department of Mathematics, Haramaya University, Harar, Ethiopia

10.22075/ijnaa.2025.37143.5420

Abstract

Dengue is a serious disease that poses a threat to humans in tropical and subtropical regions globally. The disease is transmitted by Aedes type of female mosquitoes, which are highly sensitive to climate change, as changing climate conditions facilitate both pathogen growth and mosquito reproduction. In this study, we investigated how climate variables, especially temperature and rainfall, affect dengue transmission to model disease outbreaks. We developed a deterministic model incorporating temperature and rainfall as climate-related factors, to predict how climate change affects dengue transmission dynamics, thereby supporting public health strategies. We also derived the basic reproduction number ($R_{0}$), along with stability analysis to determine the system's steady-state behavior. The disease-free equilibrium is stable when $R_{0}$ is less than one, while an endemic equilibrium indicates the disease persists in the community. Moreover, we examined how sensitive parameters influence $R_{0}$. Unmanaged temperature and rainfall can significantly intensify dengue outbreaks. Human activities that increase carbon dioxide levels may raise temperatures, further exacerbating the situation. Our simulations show that temperatures between 20 and 30.8 degrees Celsius and rainfall below 50mm can cause an uptick in the mosquito population, which ultimately leads to dengue cases and deaths. The model is also validated using real data and found to be the best fit. Overall, the climate changes at these thresholds can result in a larger mosquito population, increasing the spread of dengue. This model offers a numerical basis for predicting how climate variables impact dengue transmission dynamics.

Keywords

Dengue transmission

Impact of Climate

Aedes aegypti

Vector-born disease

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