Bird flu outbreak in wild birds?

Today my colleague noticed a flock of dead sparrows on the ground.
He and I have never seen this before and I saw one of the dead birds. The cleaner for the area had swept up about 20 of them together.
It looks like the HN51 bird flu killed them off but Taiwanese authorities keep claiming it is another weaker variant…yeah right. It seems to be very similar to what they described in China, as in flocks dropping from the sky. Some people suggested poison could do this, but it’s kind of an amazing coincidence for this to happen during the bird flu outbreak (neither of ever witnessed this mass death before). It is also an outside chance that west nile virus is responsible.

Has anyone else seen a group of dead birds lately?