If it's just a few sporadic birds dying off, people are then exposed and then get sick and die -- it means it's a very difficult thing to stop when it's on a small scale.
Migratory birds are a pretty common reservoir of avian flu, although it would be hard to confirm the link,
The important thing is how the authorities handle the outbreak, how swiftly it is addressed and how quickly birds are culled. China in that practice has plenty of experience, so we are confident from the animal point of view the outbreaks are tackled as quickly as they can be.