Effects of climate change on Plasmodium vivax malaria transmission dynamics: A mathematical modeling approach

Abstract

Malaria is a major public health concern and an economic burden around the world. Currently, malaria has been declared as endemic in 91 countries. Every year more than 200 million cases of malaria are reported and more than US$2 billion has been invested in malaria control. Recent climate change caused by global warming has affected the pattern of malaria outbreak and expanded the endemic regions. In this study, we develop a malaria transmission model associated with climate-dependent parameters. We analyze the impact of climate change on malaria transmission using climate data based on Representative Concentration Pathways (RCP) scenarios. We investigate the potential risk of malaria outbreaks through the computation of seasonal reproduction number and vectorial capacity under RCP scenarios and perform a sensitivity analysis of the model parameters. Our region of focus is the northern part of South Korea where Plasmodium vivax malaria is currently endemic. Our results show that climate change will increase the risk of massive malaria outbreaks in the area. Furthermore, based on the actual incidence data, we estimate the parameter values that reflect the level of controls implemented recently in Korea. We found that the current level of controls is not sufficient to mitigate the effect of climate change on malaria outbreaks and a combination of stronger control measures such as at least a 10% increase of control for humans combined with a 5% increase of control for adult mosquitoes should be implemented to reduce the risk of malaria outbreaks.