Amid rising respiratory illnesses, a CDC report reveals undetected bird flu cases in US veterinarians. The spread, shown through antibody tests, indicates infections occurring beyond known zones. Experimental confirmation of H5N1 transmission through cow milk prompts officials to urge all states to join the national milk testing program.

With so much H5N1 circulating in the U.S., scientists worry we are a few mutations away from a potential human pandemic.

A recent study by the Centers for Disease Control and Prevention (CDC) that was supposed to be made public weeks ago, but was withheld because President