Impacts on Public Health

Chapter Summary: While climate change can have a variety of public health consequences, it is important to remember that many other factors also play important roles in health outcomes. Even direct effects of climate change, such as heat waves, are worsened in urban settings and ameliorated with green spaces and air-conditioned refuges. The challenge of projecting health outcomes from climate change decades into the future is significantly more complicated for diseases transmitted from animals to humans. For example, housing close to forests, animal husbandry close to bird migration pathways, transport of live animals and human mobility can have significantly more impact on the risk of pandemics than climate change leading to the change in the natural habitat of animal hosts or disease vectors. This chapter begins with a general discussion of these issues and then describes work we did in collaboration with area experts from the World Health Organization which resulted in a book on The Contextual Determinants of Malaria (RFF Press, 2002). The chapter then describes work on the role of climate change in the spread of West Nile virus, and cryptosporidiosis, the former being a mosquito-borne disease and the latter a water-borne one. As with malaria, the role of climate change is only one of many factors determining the extent and severity of disease outbreaks.