The impact of climate change on human health: some international implications.

The objective of this study is to discuss the potential impact of a global warming on various aspects of human health. Changes in heat-related mortality are estimated for four countries: the United States, Canada, the People's Republic of China and Egypt. In addition, the potential confounding impact of increased air pollution is considered. Finally, a framework to analyze two vector-borne diseases, onchocerciasis and malaria, which may spread if temperatures increase, is discussed. Our findings suggest that heat-related mortality is estimated to rise significantly in all four countries if the earth warms, with the greatest impacts in China and Egypt. The most sensitive areas are those with intense but irregular heat waves. In the United States, air pollution does not appear to impact daily mortality significantly when severe weather is present, although it seems to have a slight influence when weather conditions are not stressful.