Quick Guide: Bird flu
Printable version
Global threat

Evolving menace

Virus origins

Human dimension

Fighting the virus

Evolving menace

A primary concern is if people already suffering from a human strain of flu contract the avian virus.

The viruses could join to create a previously unknown version not yet recognised by human immune systems.

The new variant is likely to spread quickly and easily, triggering a deadly pandemic.

Experts predict it could kill more than 2m people and infect millions more.