Drivers of emerging zoonotic infectious diseases

This chapter discusses drivers of emerging infectious diseases (EID) of humans that have an origin in other vertebrate animals (zoonoses). This is a broad topic, worthy of a book in its own right. This chapter will therefore provide only an overview of key concepts of drivers of the emergence of zoonotic diseases, and particularly infectious diseases with a major disease burden in humans. As the authors mainly work in Asia, the focus of this chapter is Asia, but many of the lessons learned in this region are likely to apply elsewhere. More than 60 % of the world population live in Asia, a region with some of the fastest developing economies in the world. Yet, despite tremendous advances, infectious diseases still remain a major burden for the human population in Asia. Of the estimated 2.1 million deaths in children aged less than 5 years in Southeast Asia in 2010, 47 % are attributable to infectious causes (Liu et al., Lancet 379:2151-2161, 2012). As such, Asia is both vulnerable to imported EIDs and a global focus of major social and environmental change that may facilitate the emergence and dissemination of new pathogens. However, it would be too simplistic to present the extensive changes in Asia as inevitably increasing the risk of EIDs. Some aspects of socio-economic change might serve to reduce the overall risk of infectious disease emergence, but all ecosystem changes have the potential to provide new opportunities for microorganisms to spill-over into human populations.