It's those birds in cages!
For instance, yesterday's CNN.com piece links the spread of the H5N1 strain to domestic birds, not migratory ones. The article is a good long one, by online standards. Here's a sample to whet your appetite.
Since the early fall, however, there have been only scattered reports of more outbreaks. The disease has been glaringly absent, for example, from western Europe and the Nile delta, where many presumed it would crop up as migrating birds returned to winter roosts.Read it all. Click on the NWHC link above, and stay abreast of developments. If we're informed, we can counteract those doomsayers.
That suggests the strain has evolved to specifically exploit domestic poultry, whose short lives spent in tight flocks mean a virus has to skip quickly from bird to bird if it is to survive, said Hon Ip, a virologist with the U.S. Geological Survey's National Wildlife Health Center in Madison, Wisconsin.
That also means that while the virus can pass from domestic to wild birds, the latter may not be suited as transmitters of the strain -- at least so far.
"By the timing of the spread and the pattern of outbreaks within a country and between countries, it does not make sense relative to a role for migratory birds as a means of spreading the virus," Ip said.