Hot topic or hot air? Climate change and malaria resurgence in East African highlands

doi:10.1016/S1471-4922(02)02374-7

Trends in Parasitology

Volume 18, Issue 12, 1 December 2002, Pages 530-534

https://doi.org/10.1016/S1471-4922(02)02374-7 Get rights and content

Abstract

Climate has a significant impact on malaria incidence and we have predicted that forecast climate changes might cause some modifications to the present global distribution of malaria close to its present boundaries. However, it is quite another matter to attribute recent resurgences of malaria in the highlands of East Africa to climate change. Analyses of malaria time-series at such sites have shown that malaria incidence has increased in the absence of co-varying changes in climate. We find the widespread increase in resistance of the malaria parasite to drugs and the decrease in vector control activities to be more likely driving forces behind the malaria resurgence.

Section snippets

Evidence for possible causes of malaria resurgences

Since the early 1980s, there have been massive percentage increases in P. falciparum burden at African highland locations (Fig. 1). Possible causes are discussed below.

The most parsimonious explanation

The evidence that climate change is the most significant factor in recent malaria resurgences in the highlands of East Africa is at best equivocal, at worst unfounded. At five of the seven sites (Kericho, Kabale, Gikonko, Muhanga and Amani), climate has not changed significantly. At the two other sites, where malaria up-surges were most marked (Debre Zeit and Analaroa), temperatures have shown significant long-term increases; however, the collapse of vector control at these sites shows equally

Policy considerations

The threat from climate change is not a top priority for African nations faced with a contemporary resurgence in malaria. Our hope is that the research reviewed here might help focus attention on the real and immediate causes of these malaria resurgences, rather than fuel further speculation on the future epidemiological impacts of climate change. Although predictions of the impact of forecast climate surfaces [e.g. the high scenario from the HadCM2 experiment described on the Intergovernmental

Acknowledgements

S.I.H. is supported as an Advanced Training Fellow by the Wellcome Trust (#056642) and is affiliated to the Kenya Medical Research Institute/Wellcome Trust Collaborative Programme, PO Box 43640, Nairobi, Kenya. S.E.R. is a Natural Environment Research Council (UK) Senior Research Fellow (#341). J.C. is supported by the Dept for International Development, UK. G.D.S. is supported by the US Army Medical Research and Materiel Command, Ft Detrick, MA, USA. The opinions and assertions contained

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Trends in Parasitology

OpinionHot topic or hot air? Climate change and malaria resurgence in East African highlands

Abstract

Section snippets

Evidence for possible causes of malaria resurgences

The most parsimonious explanation

Policy considerations

Acknowledgements

Trends Parasitol.

Lancet

Global Environ. Change

Curr. Opin. Microbiol.

Trends Immunol.

Trans. R. Soc. Trop. Med. Hyg.

Trends Parasitol.

Trans. R. Soc. Trop. Med. Hyg.

Lancet

Trends Parasitol.

Acta Trop.

Lancet

Trans. R. Soc. Trop. Med. Hyg.

Trans. R. Soc. Trop. Med. Hyg.

Parasitol. Today

Adv. Parasitol.

Trans. R. Soc. Trop. Med. Hyg.

Trans. R. Soc. Trop. Med. Hyg.

Adv. Parasitol.

The ears of the hippopotamus: manifestations, determinants, and estimates of the malaria burden

Am. J. Trop. Med. Hyg.

Climate Change 2001: The Scientific Basis – Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change

Ecological responses to recent climate change

Nature

Global climate change and emerging infectious diseases

J. Am. Med. Assoc.

Effects on biological disease agents

Climate Change and Human Health

Biological and physical signs of climate change: focus on mosquito-borne diseases

Bull. Am. Meteorol. Soc.

Malaria in the African highlands: past, present and future

Bull. WHO

Opinion
Hot topic or hot air? Climate change and malaria resurgence in East African highlands