There’s an outbreak of dog flu affecting at least 11 states. After inundating Chicago with flu and bouncing around the country in 2015 and 2016, the H3N2 virus, which arrived from Southeast Asia, took a lower profile. But, clearly it never went away. Last month, the H3N2 dog flu virus popped up again, and in a big way. The epicenter might have been two dog shows.
Guesstimates are that 300 or more dogs have been infected with H3N2. Approximately 30 to 40 cases have been confirmed via diagnostic labs. Also, there are several confirmed fatalities.
States with confirmed H3N2 are currently Florida, Georgia, Kentucky, Louisiana, Missouri, North Carolina, South Carolina, Tennessee, California, Illinois, and Texas. Some states appear to have only a few sick dogs, while others have many more. Many argue that H3N2 is endemic in the Chicago area, which means it may linger in the environment for a long time.
Dr. Jerry Klein, chief veterinary officer at the America Kennel Club (AKC) says it appears that this all began at dog shows in Perry, Georgia, and DeLand, Florida. No one will ever likely pinpoint how that happened. However, it’s not surprising to Dr. Cynda Crawford, clinical assistant professor at the University of Florida College of Veterinary Medicine in Gainesville. “H3N2 is in the environment and could have been brought into the shows in any number of ways. Because there’s no immunity to the virus, which is novel in the U.S., most dogs exposed get the virus.”
Klein happens to be from Chicago, where H3N2 first hit, and he was at ground zero for the outbreak. He suggests what happened at the dog shows was similar. “At first, people assumed it was kennel cough, which is a nuisance but not awful. But, just as in Chicago, some dogs got significantly sicker. And we began to think about the dog flu pretty quickly.”
And that fallout is happening now. When the dog flu, or canine influenza virus (CIV), hits neighborhood boarding or grooming facilities, or local dog parks, the contagious dogs bring the virus back home with them. Because dogs at AKC shows are often states away, the bug has quickly spread.
The response within the dog show world has been swift. More than 200 dogs reportedly pulled out of the May 26-29 Blue Ridge Classic Dog Show, held near Asheville, North Carolina. And, the Kennel Club of Texarkana 50th Anniversary Dog Show, which was scheduled for June 17-18, has been cancelled.
“Many handlers I know are getting their dogs vaccinated, and waiting the two to four weeks for the booster before working any show,” says Dr. Scott Tritsch of Georgetown, Kentucky. He says he’s currently dealing with a group of 39 sick dogs that presumably have the dog flu. Among the dogs he’s treating are nine two-week-old puppies. “Yes, still alive, but not out of the woods quite yet,” he says
Dr. Richard Hawkes of Morehead City, North Carolina, noticed that two of his black Russian terriers began to cough and run fevers shortly after returning from the Perry Dog Show. Within just a few days, all of his 10 dogs were exhibiting similar symptoms. Diagnostic testing confirmed H3N2. Those who exhibit dogs see no reason to test all when it’s so likely they all have the same thing. It’s one reason there’s such a dramatic discrepancy in numbers between the dogs confirmed with H3N2 via a diagnostic lab and those presumed to have H3N2. Why test them all?
Another explanation for the disparity is the cost of testing. Medically, encouraging the diagnostics is important. Clearly, veterinarians should know specifically what’s going on with a dog. Is it canine infectious respiratory disease complex (such as Bordetella or canine parainfluenza), or is it canine influenza virus or even a co-infection? It’s also important to get a grasp on what’s happening in a community. However, convincing pet owners the of the need to know this information can be challenging since treatment is often the same. And treatment, of course, begins instantly. No one wants to wait for the test results to come back.
“I get it,” says Klein. “When income is limited, I’d rather see the client spend dollars on treatment.”
Another issue might be that some exhibitors are afraid or embarrassed to mention their dog has flu, and some might recklessly travel to events with sick dogs. Klein maintains these are exceptions. He says that, in his experience, people are sharing information openly far and wide via social media. In fact, if anything, there may be some exaggeration. Via Klein, the AKC has been what some have described as “uncharacteristically transparent.” From the start, Klein (and therefore the AKC) has collaborated with medical partners, including the American Veterinary Medical Association (AVMA).
The H3N2 virus continues to have an extremely high morbidity—making many exposed dogs sick—and a low mortality—approximately three to five percent affected will die.
But even if it’s a small percentage, dogs are dying as a result of the dog flu. Hawkes lost one of his black Russian terriers, though he’s quick to point out that his dog did have additional medical issues.
“It was pretty scary to see my 10 big dogs taken down in a matter dog days,” Hawkes observes.
Scarier yet is what Dr. Eward Dubovi, director of virology section at the Animal Health Diagnostic Center at Cornell says, “We are sequencing all the time to determine if the H3N2 virus diverges into different clades (almost like sub-strains of flu). If that happens, it doesn’t mean that the vaccine won’t be effective, but it’s something to pay attention to.”
Dubovi says he not surprised by the fast spread of H3N2 because it is more contagious than H3N8, which was the strain of dog flu first identified in Florida back in 2008 after mutating from an equine flu into a dog flu.
The other problem with H3N2? For an influenza virus, it’s is somewhat hardy, and can live on objects, like shoes or a veterinarian’s stethoscope, and be transported. Also, about 20 percent of infected dogs feel great and never have a single symptom but remain as infectious as the sick dogs. That is great for those individuals who are up to chasing squirrels, but their owners have no way to know their dog is contagious.
The good news is that show dogs often don’t intermingle in the community, they likely stay at home or are on the road. However, that’s not always true. And anecdotally, it seems clear, at least some dogs now being diagnosed with H3N2 have never participated in a dog show and have never associated with show dogs. In at least some communities, the virus might have spread into the general population. So far, though, there are no confirmed reports of the flu hitting a shelter or overwhelming a single community (like what occurred in Chicago).
Unfortunately, the setting is ripe for a perfect dog flu storm. Not only is dog show season ramping up, so is travel season. Even more threatening than dog shows are people about to head for vacations and their dogs will be boarded in spaces more susceptible to CIV transmission than a dog show, particularly when kennels offer dog play groups.
Crawford says there are only two best methods of protection from CIV: Either dogs are completely anti-social or they are vaccinated. Crawford says if it was up to her, “You vaccinate all the show dogs, absolutely. This is the primary tool, it doesn’t matter if you’re talking people, dogs, horses, or pigs. Vaccination is the strategy.”
As an exhibitor himself, Hawkes notes that vaccination is a worthy investment compared to the cost of treating many dogs. And, as it turns out, one of his dogs paid the ultimate price.
The AKC is indeed doing all they can possibly do to inform handlers and exhibitors, and have created a hand-out with all the latest information on CIV transmission, symptoms to watch for, and hygiene to minimize risk. The notice clearly indicates, “The best protection is vaccination.”
But should the AKC mandate the vaccine for CIV (either for H3N2 specifically or the bivalent vaccine for H3N2 and H3N8)?
Tritsch says, “This is a big deal, not only for the dogs in the AKC shows and events, but for the communities the dogs return to.”
Dubovi has the million-dollar question, which he concedes requires a crystal ball to answer. Will the outbreak worsen or fizzle out on its own? “I don’t know, but I do know dogs have died, even if it is a small percent.”
Hawkes says, “The AKC needs to push now for all dogs to be vaccinated, and, if your dog has been exposed, please don’t show for 30 days. The problem is that people may not know if their dog was exposed.”
Dr. Ronald Schultz, professor of pathobiological sciences at the University of Wisconsin School of Veterinary Medicine in Madison contributed to the American Animal Hospital Association Canine Vaccination Guidelines and has always spoken out against over-vaccination. He says, “Dogs at risk should be vaccinated at least yearly with both influenza strains, H3N8 and H3N2, in addition to the other causes of canine cough.”
Klein concludes, “It’s tough. If we close for 30 days as some have suggested, on day 31 the flu may appear. That really doesn’t seem to be the answer. Certainly, we endorse and encourage people to make their own choices based on all the information we can openly provide. And, absolutely discuss this with your own veterinarian. If there’s a human influenza virus in New York City, and you get coveted tickets to a Knicks game or a Lady Gaga concert, do you still go? It’s a personal decision.”