Swine flu: diffusion across the world
From late April 2009 onward, World Health Organization (WHO) has been updating regularly the global Swine Flu situation on a country level. This series of Map Library maps shows the diffusion of the virus on a week-by-week basis. Week One refers to the one week period beginning 20 April 2009 whereas Week Eleven refers to the week beginning 29 June (WHO stopped the regular updating after 6 July). At a specific week, countries reporting their first cases are represented by the blue dots. Afterwards, these countries (infected countries) are shaded black. Over a period of less than 3 months, the virus has diffused through a large proportion of the inhabitable world. The maps were created following re-organization of data from the WHO and other sources, obtained through the update files of Centre for Health Protection, Hong Kong Special Administrative Region Government.