Thursday, August 5, 2010: 10:00 AM
Blrm A, David L Lawrence Convention Center
Background/Question/Methods The impact of climate change (and climate variability) on malaria is most relevant in geographical regions at the edge of the distribution of the disease, where its population dynamics exhibit epidemic outbreaks or ‘unstable’ behavior. It is in these regions, highlands and desert fringes around the tropics, that temperature or rainfall limit transmission. Despite it’s obvious importance to the populations living in these areas, the impact of climate change on epidemic malaria continues to be vigorously debated. Some authors have even denied a role for climate change using a series of arguments that imply a lack of evidence for an effect of warmer temperatures and the alternative importance of other factors such as the spread of drug resistance. We present a synthesis and criticism of these arguments, based on our recent work on the effect of the observed warming during the past three decades in East African highlands and on the non-independence of warmer temperatures and the spread of drug resistance. We ask more generally how do population models of transmission help us address questions on climate change and disease.
Results/Conclusions Arguments against a role of climate change on epidemic malaria in E. African highlands are flawed. Neither warmer temperatures, nor the spread of drug resistance, appear sufficient to explain the increases of malaria incidence observed in the last three decades. There is evidence, however, for a significant effect of temperature increases, although challenges remain to better quantify the magnitude of this effect, its uncertainty and its interplay with other trends. Population models of disease have an important role to play in retrospective and prospective analyses of climate impacts, to move us beyond the non-constructive debate between ‘deniers’ and ‘alarmists’. Open areas are outlined in terms of where we stand today, including the important connection between climate change and climate variability.
Results/Conclusions Arguments against a role of climate change on epidemic malaria in E. African highlands are flawed. Neither warmer temperatures, nor the spread of drug resistance, appear sufficient to explain the increases of malaria incidence observed in the last three decades. There is evidence, however, for a significant effect of temperature increases, although challenges remain to better quantify the magnitude of this effect, its uncertainty and its interplay with other trends. Population models of disease have an important role to play in retrospective and prospective analyses of climate impacts, to move us beyond the non-constructive debate between ‘deniers’ and ‘alarmists’. Open areas are outlined in terms of where we stand today, including the important connection between climate change and climate variability.
