Dogs can get the flu – but can’t share it with humans

The city of San Francisco and the province of Ontario, Canada, are the two latest areas where canine flu is making an appearance. The virulent respiratory disease has hopscotched the continent, with only four states remaining free of it: Alaska, Hawaii, Nebraska and North Dakota. Where it lands depends in large part on how social and mobile dogs are in particular areas.

“Dogs that travel are at risk, and dogs exposed to dogs who travel are at risk,” says veterinarian Cynda Crawford, a canine flu expert at the University of Florida College of Veterinary Medicine. Other dogs who are vulnerable are service dogs, police dogs, show or competition dogs, shelter dogs and dogs who visit dog parks, groomers or boarding kennels on a regular basis.

The two strains of canine influenza, H3N2 and H3N8, can infect dogs at any time of year, not just winter. Although she hasn’t seen many cases of the flu in her own practice, internal medicine specialist Lawren Durocher-Babek, medical director at Red Bank Veterinary Hospital in Hillsborough, New Jersey, says the flu seems to be worse in midwinter as well as late summer and into fall.

“However, it can be seen at any time of year, so it should always be on our radar,” she says.

If you’ve seen in the news that humans are being hit hard by the H3N2 flu virus and then you see that dogs also get H3N2, you may be concerned that you could catch the flu from your dog. Fortunately, that’s not possible, says virologist Edward Dubovi, a professor in the department of population medicine and diagnostic sciences at Cornell University College of Veterinary Medicine in Ithaca, New York.

Think of influenza viruses as automobile types, he says. A brand of sedans, pickup trucks and convertibles may all be made by the same manufacturer, but they all have different profiles and accessories. Flu viruses are the same way: There are H3N2 human viruses, H3N2 pig viruses, H3N2 dog viruses and H3N2 avian viruses.

Dogs do not transmit canine influenza to humans, but in at least one instance, cats in an Indiana shelter acquired H3N2 canine flu from dogs. Cats can also transmit influenza to each other. And although it is rare, your dog or cat may pick up human influenza virus from you.

“Pet owners sick with the flu should take care to avoid possible transmission to their pets,” says Dr. Christiane V. Loehr, a veterinary pathologist and associate professor at Oregon State University Carlson College of Veterinary Medicine.

Suspect that your dog has the flu because he’s coughing, sneezing and feverish? Don’t just walk him into your veterinarian’s lobby, where he could spread the infection to other pets. Alert your veterinarian beforehand so your pet can be examined in the car or taken to an isolation area through another door.

Dogs diagnosed with canine flu should be isolated from other pets for longer than you might think: at least 21 days, and perhaps even a month. Wash your hands thoroughly after caring for a dog with the flu before interacting with other animals. Disinfect dishes and bedding separately, too.

If your dog is one of those at risk – a social butterfly or a road warrior – or has physical characteristics such as a flat face or narrow nostrils that could make it difficult for him to breathe in the event of a respiratory ailment, consider getting him vaccinated for canine flu. “The vaccine may not stop a dog from getting the flu, but it has been shown to decrease severity of signs and shedding (of the virus),” Dr. Durocher-Babek says.

Pet Connection is produced by a team headed by veterinarian Dr. Marty Becker and Kim Campbell Thornton, author of many pet-care books. The two are affiliated with