It's not just people and pigs, anymore. Washington Post blog The Checkup reports that a cat in Iowa has tested positive for the H1N1 virus, "marking the first time a cat has been diagnosed with this strain of influenza," according to state officials. The 13-year-old cat is believed to have caught the illness from one of the two humans in its household who battled swine flu. All members of the household, including the cat, recovered. H1N1 has now been documented in cats, humans, pigs, birds, and ferrets.