Bird flu is affecting a growing number of cattle herds in the US, and these infections have led to only the second known human case in the nation, according to the US Centers for Disease Control and Prevention. There has been no human-to-human spread in the US, but there have been sporadic cases of people sharing the bird flu virus in other parts of the world, so the CDC says it is watching the situation closely. Like all viruses, H5N1 has the potential to mutate to become more of a threat to... Read this story
