Bird flu outbreak more virulent than ever recorded - study
While the viruses' risk to humans remains low, the researchers noted only a few amino acid changes are needed for that to change.
Chickens await vaccination against bird flu at the settlement Peredovoi 100 km (62 miles) from the Russia's southern city of Stavropol, March 11, 2006.(photo credit: EDUARD KORNIYENKO/REUTERS)ByTZVI JOFFREUpdated: