Flu facts: What the virus means for humans

What is bird flu?

Bird flu is an infectious disease of birds caused by a variant of the standard influenza A virus.

Since mid-December 2003, a growing number of south east Asian countries have reported outbreaks of bird flu in chickens and ducks. The virus can spread rapidly through flocks of domestic poultry. It is the H5N1 strain which is infecting humans and causing high death rates.