Central Afrika is also the place where apes live in relative closeness to humans - and it is easy to see how we could be susceptible to viruses common to a biologically close species, especially if we are so dumb to eat them.

But the regular outbreaks of bird flu show, that this is not limited to one specific location. With the bird flu, its the markets in Asia, where close contact between poultry and humans creates regular transition of viruses to humans. Fortunately, recent more strict regulations seem to have reduced the bird flu outbreaks.