DES MOINES, Iowa (AP) -- A 13-year-old Iowa cat has been infected with swine flu, veterinary and federal officials said Wednesday in what is believed to be the first case of the H1N1 virus in a feline in the United States.

The domestic shorthaired cat was treated last week at Iowa State University College of Veterinary Medicine in Ames and has recovered, officials said. The virus also has been confirmed in two ferrets -- one in Oregon and the other in Nebraska -- but they died.

"We've known certainly it's possible this could happen," said Centers for Disease Control spokesman Tom Skinner. "This may be the first instance where we have documentation that transmission occurred involving cats or dogs."

The veterinarian who treated the cat, Dr. Brett Sponseller, said two of the three people in the cat's Iowa home had flu-like symptoms before the cat became ill. The case was confirmed at both Iowa State and the U.S. Department of Agriculture.

Other influenza strains have been known to cross species, but Sponseller cautioned against drawing too many conclusions from the cat including whether other pets could also get the swine flu.

"It's well documented in influenza in general, but this is the first highly suspected case of H1N1 going from humans into a cat," he said.

The indoor cat was lethargic, had a loss of appetite and appeared to have trouble breathing after it became infected, Sponseller said. It's owners declined to comment.

Officials said pet owners should take the same precautions against spreading swine flu to pets as they would with humans.

Getting children vaccinated for swine flu can also help prevent the illness from spreading to pets. There is no swine flu vaccine for pets.

Dr. Ann Garvey, Iowa's state health veterinarian, said it is not yet known how sick cats or other pets could get from swine flu.

"Because we haven't seen that many cases, it's difficult to give a blanket assessment on how sick it can make an animal," she said.

Copyright 2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.