Bird flu has been found in a pig for the first time in the U.S.

The discovery of an infected pig at a backyard farm in Oregon raises concerns about bird flu's potential to become a human threat.

Bird flu has been found in a pig for the first time in the U.S.
A 2005 electron microscope image shows an avian influenza A H5N1 virion. A pig at an Oregon farm was found to have bird flu, the U.S. Department of Agriculture said Wednesday.

The discovery of an infected pig at a backyard farm in Oregon raises concerns about bird flu's potential to become a human threat.

(Image credit: Cynthia Goldsmith, Jackie Katz)