Bird Flu Virus Mutating into Human-Unfriendly Form

And we had forgotten about this potential cataclysmic threat. Problems don't go away by ignoring them:

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.

[...]The H5N1 avian flu virus, which mostly infects birds, has since 2003 infected 329 people in 12 countries, killing 201 of them. It very rarely passes from one person to another, but if it acquires the ability to do so easily, it likely will cause a global epidemic.