America is heading into an even higher-risk period as the seasonal flu begins to circulate. This also raises a question of ...

The agency, in its latest update released Thursday, said the mutations were not found in samples taken from wild birds, ...

There's a new concern that the virus could evolve to spread from human to human.

The virus in the first severe human bird flu case in the U.S. was found to have mutated. Newsweek's live blog is closed.

ALEXANDRIA, La. (KALB) - The bird flu virus in a patient in Louisiana has likely mutated while they were in the hospital.

A new mutation and the first severe case of H5N1 bird flu discovered in a human in Louisiana has raised concern among some ...

The virus has spread among dairy cattle, humans and other mammals. But officials say the current public health risk is low.

The bird flu virus found in a severely ill patient hospitalized in the United States has mutated to become better adapted to ...

The CDC has confirmed a total of 66 human cases of bird flu across the United States as of Friday, although the number is ...

Genetic analysis suggests the bird flu virus has the capacity to mutate in ways that could make it more transmissible to ...

Tiny genetic alterations could help the bird flu virus enter cells in the upper respiratory tract, the C.D.C. said. But there ...

Samples from a hospitalized patient in Louisiana show changes that could make the H5N1 virus spread more easily between ...