Bird flu infects third US dairy worker; Michigan set to expand testing

A third U.S. dairy worker tested positive for bird flu after exposure to infected cows, and was the first to suffer respiratory problems, U.S. officials said on Thursday.

The infection was the second human case in Michigan, which has confirmed more cases of bird flu in dairy cattle than any other state. It also expands the symptoms for human cases, after the two workers who previously tested positive experienced only conjunctivitis, or pink eye, and recovered.