NEW YORK (Reuters) – The H5N1 bird flu virus has mutated to infect people more easily, although it still has not transformed into a pandemic strain, researchers said on
Thursday.
The changes are worrying, said Dr. Yoshihiro Kawaoka of the University of Wisconsin-Madison.”We have identified a specific change that could make bird flu grow in the upper respiratory tract of humans,” said Kawaoka, who led the study.