Global Climate Changes and International Trade and Travel: Effects on Human Health Outcomes

There is now near-unanimous scientific agreement that greenhouse gas emissions generated by human activities have increased global temperatures and changed the earth's climate. There is, however, no universal agreement on how rapidly, regionally, or asymmetrically the earth will warm; or on the true impact of global warming on infectious disease outbreaks and natural disasters and their inevitable public health outcomes. In addition, many other factors influence the emergence and reemergence of infectious diseases in a changing environment including international trade and travel, exotic eating habits, lifestyle and residential choices, host susceptibility, and microbial adaptation. The ultimate effects of climate changes and the increased distribution of pathogens by international trade and travel will not be limited to infectious disease outbreaks in immunologically naïve populations but will also impact world food production and quality, air quality, drinking water availability and quality, immigration, urban relocation, and civil unrest. Despite the uncertainties in outcomes and their magnitudes, the active responses to climate changes in a global economy must include combinations of environmental, political, regulatory, socioeconomic, and public health measures.