Mapping the #H7N9 avian flu outbreaks | Declan Butler (Nature)
▻http://www.nature.com/news/mapping-the-h7n9-avian-flu-outbreaks-1.12863
Flight routes from the outbreak regions would quickly carry any human-transmissible virus to huge population centres in Europe, North America and Asia. Estimated numbers of people residing within two hours’ travel time of destination airport calculated using gridded population-density maps and a data set of global travel times. Map supplied by A. J. Tatem, Z. Huang and S. I. Hay (2013). Unpublished data. (A.J.T., University of Southampton, UK; Z.H., University of Florida, Gainesville; S.I.H., University of Oxford, UK.)