Epidemic malaria and warmer temperatures in recent decades in an East African highland

University of Groningen, CEES, Haren, The Netherlands.
Proceedings of the Royal Society B: Biological Sciences (Impact Factor: 5.05). 11/2010; 278(1712):1661-9. DOI: 10.1098/rspb.2010.2020
Source: PubMed


Climate change impacts on malaria are typically assessed with scenarios for the long-term future. Here we focus instead on the recent past (1970-2003) to address whether warmer temperatures have already increased the incidence of malaria in a highland region of East Africa. Our analyses rely on a new coupled mosquito-human model of malaria, which we use to compare projected disease levels with and without the observed temperature trend. Predicted malaria cases exhibit a highly nonlinear response to warming, with a significant increase from the 1970s to the 1990s, although typical epidemic sizes are below those observed. These findings suggest that climate change has already played an important role in the exacerbation of malaria in this region. As the observed changes in malaria are even larger than those predicted by our model, other factors previously suggested to explain all of the increase in malaria may be enhancing the impact of climate change.

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Available from: David Alonso, Oct 03, 2015
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    • "& See [36]; % 1: chosen from literature and fixed constant, and 2: chosen from literature and fitted. "
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    • "The role of temperature on malarial epidemics was demonstrated by a retrospective study of malarial cases in the highland region of East Africa from 1970 to 2003 [3]. This study found an association between malaria epidemics and warmer temperatures, although the predicted size of the epidemics was smaller than what actually took place. "
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    • "The second module of the model tracks the dynamics of the mosquito population (Fig. 2) and follows closely the general representation in Alonso et al. (2011). This subdivides the vector population into larval (L) and adult stages (M) and further subdivides the adult mosquitoes into three classes for uninfected X, infected V and infectious W individuals, respectively, so that M = X + V + W. The larval birth rate depends on the intrinsic growth rate of larvae F, the density of adult mosquitoes M, and the carrying capacity K. "
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