What is the scope of the sector? What issues should be included? The scope covers all direct and indirect effects of global change on human health, including the effects of air pollution coupled with heat stress; environmental and occupational exposures related to new technologies and changing patterns of use of old technologies; expanded ranges of infectious diseases; reduced biodiversity; changes in the food supply and the quality and quantity of water; and the effects of changes in weather extremes.

What are the overlaps and synergies with other sectors? Information will be needed about food availability, water availability and quality, land use and ecosystems, population demographics and economic status, social services, energy use, and commerce, industry and trade.

What are the key current and expected future (non-climatic) stresses on health? Poverty, emerging and antibiotic-resistant infectious diseases, and environmental and occupational exposures that affect human health, particularly those that cause developmental problems or chronic disease, are continuing and growing concerns. Also of concern are expected rises in chronic diseases and diseases of older age as the world's life expectancy increases.

How will climate change and variability exacerbate or ameliorate these stressors? What new stresses might be introduced? Indirect effects of global warming on human health include redistribution of the food supply as crop and forest ranges change and animal reproductive performance adjusts; migration of human populations as regional climates respond to warming in various ways; increased range for temperature-sensitive pests from killer bees and fire ants through fungi (aflatoxins), weeds, and the mosquitoes that carry malaria, Dengue fever, yellow fever and encephalitic disease, to the pathogens like cholera; increased air pollutant exposures leading to increased pulmonary damage and toxicity; and loss of biodiversity with the resulting impact on the food chain and on health consequences from new technologies, materials, manufacturing processes, and chemical mixtures. Some of these effects will be subtle, hard to detect, but possibly significant. Direct effects include heat stress coupled with increased air pollution and the effects of extreme weather events.

What are the most important information needs? There is a great need to develop better markers for the biological effects of chronic low-level exposures; evaluate human health and ecological effects of substitutes for CFCs and alternative fuels like methanol; explore ways to preserve biodiversity that is usually lost in ecoshifts of global change; evaluate the human health effects of increasing air pollution accompanying climate changes; develop better prevention (e.g., vaccines) and treatments for infectious diseases; and find more effective yet safe vector/pest control agents.

Research results will be needed on the toxicity of new and changed exposures; on biomarkers of exposure, effect, and susceptibility; on mechanisms of action of harmful environmental exposures; on mixtures, old and new; and on why some people ignore health alerts. There are monitoring and exposure assessment needs that should be planned for and prepared for ahead of any environmental change. Health care facilities will require more trained professionals for service delivery.

What coping strategies might be available to reduce climatic and other stressors? Possibilities for reducing stressors include conservation of energy resources in the transportation and industrial sectors in order to provide air conditioning without great increases in cost; improved health care prevention and delivery; improved building codes and preparation for natural emergencies; improved air and water quality; protection of biodiversity in fragile ecosystems; use of agricultural practices and technologies adapted to a changed environment.