The 1918 flu, Sars, swine flu: check out these maps on how they spread.
Let's start at the beginning with the the 1918 flu across the world, and then through South Africa.
Then there was the Sars scare and the fear that migratory birds might spread it across the world. Check the map of the flight paths these birds take.
Lastly, take a look at how the current epidemic of the swine flu has been spreading across the world.
Visit Health 24's Flu Condition Centre
Read all about the 1918 flu.