Climate change and human health.

The article “Apocalypse not” by Gary Taubes (News & Comment, 7 Nov., [p. 1004][1]) addresses the issue of fundamental differences of opinion among health scientists about the impact of climate on human health. While we acknowledge that there are strong differences in opinion about the potential consequences of future climate change on disease incidence and distribution, we share common concerns; we wish to emphasize that despite any differences, there are many areas where we agree. The key questions behind the climate/health research agendas are, How will climate change alter health risks, to what extent will risks be altered, and what can be done to mitigate any potential increase in health risks? At issue is not which is more important, climate factors or improved health measures; rather, it is important to assess how health risks might change in both industrialized and more vulnerable developing countries. The complexity of this public health issue entails far more uncertainty than many health hazards with which we are familiar. Impacts may occur indirectly through simultaneous disturbances of other sectors, including water supply, food production, or habitat. Thus far, scientists have found great difficult in communicating this extra level of uncertainty. We agree on the need to improve understanding of the complex relationships between climatic conditions and disease transmission dynamics. We also agree that disease incidence is influenced by multiple factors (none of us will argue that climate is the only or the most important factor). Well-designed research studies must be conducted to gain a better understanding of how these multiple factors relate to each other and how all might be influenced by climate. Identifying risk factors that influence disease transmission is a key to public health planning, and as more data from climate/health research studies become available, the influence of weather will be better understood. We recognize that extreme weather events such as those that may accompany this year's El Nino place an extra burden on sanitation and general public health systems. The early regional forecasts obtained from El Nino exemplify important new predictive capabilities that public health officials can use in their public health planning. Interdisciplinary research and interagency cooperation can go far toward improving the health risk assessment associated with climate change. Ecology-based research and monitoring combined with advances in climate forecasting will enhance our understanding of complex environmental health hazards and may provide the public with early warning systems that allow timely public health interventions. The signatories of this letter agree that public health is of great importance and that public health infrastructure and services must be improved worldwide. We recognize that environmental and socioeconomic conditions underpin health status; effective and sustainable public health prevention will ultimately require improvement in these underlying conditions. It is important to realize, however, that the projected climate change may have a profound influence on an aspects of human ecology, and we strongly recommend that research be supported to allow development of effective prevention strategies that will help mitigate its effect on public health. [1]: /lookup/doi/10.1126/science.278.5340.1004