A new, highly contagious and sometimes deadly canine flu is spreading in kennels and dog tracks nationwide, veterinarians said Wednesday.
The virus – which scientists say mutated from an influenza strain that affects horses – has killed racing greyhounds in seven states and has been found in shelters and pet shops in many places, though the extent of its spread is unknown.
Dr. Cynda Crawford, an immunologist at the University of Florida’s College of Veterinary Medicine who is studying the virus, said it spreads most easily where dogs are housed together, but it can also be passed on the street, in dog runs or even by a human transferring it from one dog to another. Kennel workers have carried the virus home with them, she said.
Linh Truong, a spokeswoman for the Colorado Department of Agriculture, said department officials are aware of the virus, but since veterinarians are not required to report cases to the state, officials don’t know of any.
How many dogs die from the virus is unclear, but scientists said the fatality rate is more than 1 percent and could be as high as 10 percent among puppies and older dogs.
Crawford first began investigating greyhound deaths at a racetrack in Jacksonville, Fla. in January 2004, where eight of the 24 greyhounds who contracted the virus died.
“This is a newly emerging pathogen, and we have very little information to make predictions about it,” she said.
She added that because dogs have no natural immunity to the virus, virtually every animal exposed will be infected. About 80 percent of dogs that are infected with the virus will develop some symptoms, Crawford said.
She added that the symptoms are often mistaken for “kennel cough,” a common canine illness.
Both diseases can cause coughing and gagging for up to three weeks, but dogs with canine flu may have fevers as high as 106 degrees and runny noses. A few will develop pneumonia, she said.