Economic growth, urbanization, globalization, and the risks of emerging infectious diseases in China: A review

Abstract

Three interrelated world trends may be exacerbating emerging zoonotic risks: income growth, urbanization, and globalization. Income growth is associated with rising animal protein consumption in developing countries, which increases the conversion of wild lands to livestock production, and hence the probability of zoonotic emergence. Urbanization implies the greater concentration and connectedness of people, which increases the speed at which new infections are spread. Globalization-the closer integration of the world economy-has facilitated pathogen spread among countries through the growth of trade and travel. High-risk areas for the emergence and spread of infectious disease are where these three trends intersect with predisposing socioecological conditions including the presence of wild disease reservoirs, agricultural practices that increase contact between wildlife and livestock, and cultural practices that increase contact between humans, wildlife, and livestock. Such an intersection occurs in China, which has been a "cradle" of zoonoses from the Black Death to avian influenza and SARS. Disease management in China is thus critical to the mitigation of global zoonotic risks.

Keywords: Avian influenza; China; Emerging infectious diseases; Globalization; Urbanization; Zoonosis.

Fig. 1

Growth of China’s poultry (a) and pig (b) stocks since 1979, compared to India and the United States

Fig. 2

The intersection of dense chicken and duck populations, human populations (concentrated by urbanization), and migratory birds increases the likelihood of interspecies transmission and the emergence of new influenza strains. Sources Generalized bird migration routes adapted from Fang et al. (2008); poultry distribution data from Robinson et al. (2014)

Fig. 3

The increasing population of the Pearl River Delta urban area (black) and the annual rise in influenza-positive specimens from Shenzhen, one of its primary cities (gray). Sources Urbanization data from Bureau of Statistics of Guangdong Province (2013); Shenzhen influenza-positive specimen data from Cheng et al. (2013)

Fig. 4

The percent increase in the volume of commodities exported from mainland China to different global regions between 2001 and 2011. Source Food and Agriculture Organization (http://www.faostat.org/)

Fig. 5

The geographic distribution of confirmed outbreaks of novel and/or pandemic influenza strains since 1900. Of the four pandemic strains, three emerged in China. Adapted from: http://www.niaid.nih.gov/topics/Flu/Research/Pandemic/Pages/TimelineHumanPandemics.aspx