In my book, I looked at the relationship between the pervasive global slum, everywhere associated with sanitation disasters, with classical conditions favoring the rapid movement of disease through human populations; and on the other side, I focused on how the transformation of livestock production was creating entirely new conditions for the emergence of diseases among animals and their transmission to humans.
Influenza is an important paradigm for infectious disease. Its ancient reservoir lies in the uniquely productive agricultural system of southern China with its long, intimate ecological association among wild birds, domestic birds, pigs, and humans. As for bird flu: On the one hand, you've created optimal conditions in the modern world for its spread; on the other hand, even the growth of poor cities has been increasing the demand for protein in people's diets and this demand can no longer be met by traditional protein sources; it's met by industrialized livestock production.
What that means quite simply is the urbanization of livestock.
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