As far as I know, there have been no cases of avian flu hummingbirds have been reported.  It seems that the wild birds that have been affected the most by the virus are raptors (e.g. hawks and eagles), and waterfowl (e.g. ducks and geese).

       However, this is not to say that hummingbirds are immune from the dreaded disease.  One of the reasons why it has not been found in wild hummingbirds could be that their life style lessens they will come in close contact birds that have a greater chance of being infected by avian flu

       If I ever hear of hummingbirds contracting avian flu, I will let you know.

Adult Male Ruby-Throated