Bird Flu is spreading around the world as fast as wild birds fly. The birds are carrying flu with them as they migrate. They infect local, non migratory birds that in turn infect local chickens, ducks, turkeys and so on.

Bird flu is spread to humans primarily by contact with chickens, ducks and other poultry. But it is also spread by contact with any other infected birds. So even if you live in the city, the local pigeons can carry bird flu to your window sill.

Humans appear to become infected with the virus not by eating infected poultry, but by contacting infected matter or preparing them for consumption.

Dust and viral particles seem to be a primary cause of human infection. "We believe those particles are inhaled and that's how people become infected." said Dick Thompson, a spokesman for the World Health Organization, in Geneva. He added, "It's very difficult to stop the movement of this virus now.