One in five commercial milk samples tested in a nationwide survey contained particles of the H5N1 virus, the U.S. Food and Drug Administration said late on Thursday, suggesting the outbreak of bird flu is more widespread than previously thought.
One in five commercial milk samples tested in a nationwide survey contained particles of the H5N1 virus, the U.S. Food and Drug Administration said late on Thursday, suggesting the outbreak of bird flu is more widespread than previously thought.