A New Flu Virus in Dogs

Federal disease detectives are alerting veterinarians around the country about a new flu virus in dogs that has spread in kennels, animal shelters and boarding facilities in three states.

Cynthia Crawford, an immunologist at the University of Florida's veterinary clinic, said the virus is highly contagious, but does not result in high numbers of deaths.

"It's not the deadly virus that certain sources have played it up to be," said Crawford. She has followed the virus since its first appearance in the United States in greyhounds at a Jacksonville, Fla., racetrack in January 2004, where eight of 24 infected dogs died.

Crawford said there have been confirmed cases of the flu in Florida, New York and Massachusetts. Although there have been reports of it being found in other states, that has not yet been confirmed.

The scientist said that in cases in which dogs have been confirmed to have the flu strain, mortality ranges from 5 percent to 8 percent, mostly from pneumonia. She said that 80 percent of dogs that get it develop mild symptoms of a nasal discharge and a cough.

Crawford said she's continuing to show her own dogs at American Kennel Club events, and take them to dog parks.

The virus has sparked scientific interest because it appears to be a rare event of a virus that jumped the species barrier from horses to dogs. There's no indication that it can be spread to humans, and scientists say they have no evidence that it can be transmitted from infected dogs back to horses.

"It's been in horses for over 40 years, and in all these years there's never been a documented human case," said Ruben Donis, an influenza investigator for the U.S. Centers for Disease Control and Prevention.

Donis said that the CDC has notified veterinarians to be on the lookout for the virus, which mimics the symptoms of an animal disease called "kennel cough" that is caused by a bacteria. But unlike animals having illnesses caused by the bacteria, dogs with the canine virus do not respond to antibiotics.

CDC scientists say tests of animal blood samples show that the transfer of the virus from horses to dogs appears to have been a relatively recent event.