Should we worry about canine influenza?

Is canine influenza just another one of the many causes of kennel cough, or something more serious?



The disease only emerged in dogs for the first time in 2004 when it was identified as the cause of serious respiratory disease in racing Greyhounds in Florida. Since then, we've learned more about it, including a recent article in Veterinary Microbiology that suggests it's both more contagious and more serious than first believed.



From my SFGate.com column today:

"We know that canine influenza, a new disease for many veterinarians, is often under- or misdiagnosed because clinical signs are similar to other respiratory diseases," said Dr. NallaKannu Lakshmanan, one of the study's authors and a researcher for [Intervet, the company that manufactures the CIV vaccine]. "Our research further suggests that infected dogs may have serious lung damage that goes undetected because it does not manifest as pneumonia."



In other words, there is evidence that the disease damages even the lungs of dogs who don't develop full-blown pneumonia -- damage sometimes missed because of the lack of obvious symptoms.



Additionally, the virus appears to be more easily transmitted than some of the other causes of canine cough.



According to Dr. Michael Moyer, director of shelter animal medicine at the University of Pennsylvania School of Veterinary Medicine, 100 percent of dogs exposed to the virus are infected by it.



"Around 20 percent of them won't have any noticeable symptoms," he said. "But they're probably shedding the virus, which can infect other dogs. And we can't do anything to prevent it because we don't know those dogs are sick."



Moyer works full-time at UPenn and also owns a private veterinary practice in Bethlehem, Pa., but he's also done some speaking on canine influenza at events sponsored by Intervet.



And the company, as the manufacturer of a vaccine for the disease, clearly has an interest in dog owners believing the worst about the virus, so like all cases of "science by press release," what they have to say should be taken with the appropriate amount of sodium chloride.



But it's probably true that the disease is under-diagnosed, and that it can be somewhat more serious than many of the other causes of canine respiratory disease, all of which have been around for a long time.



Emerging diseases are often more deadly than established ones, because the species hasn't yet adapted to resist or tolerate the pathogen.



Moreover, we don't know much about new diseases by virtue of the fact that they're just that: new. The first few years after a disease emerges, or crosses to a new species, usually involve a period of assumptions followed by corrections of those assumptions.

Read the entire article here.



Photo: Gina's Woody, who survived CIV when he was a puppy.

Comments

[Christie Keith]

I agree we need to be careful about "medicine by press release," as I say in the column. However, I get a lot of press releases. In digging into this one, I got a strong sense that we really are seeing CIV as more serious than most of the other "kennel cough" bugs. That isn't, and shouldn't be, any substitute for evidence, and I could easily be wrong. But my instincts, which are based on many years of experience, are right now going with "more serious than we thought."

So while I do think it's similar to "the new parvo" story, my educated guess is that there is some fire under the smoke on this one.

[Christie Keith]

Hi, Mary, it is... if you follow the link I give to the abstract, you can purchase the full article.

[YesBiscuit!]

Canine influenza: It's the new New Parvo!

[Liz Palika]

Riker came down with CIV after a dog show. He was an adult, and was very sick dog for a while, and had a slow recovery, but did recover fully and has had no residual problems.



I was lucky in that my veterinarian keeps up on stuff, and had been talking to other vets in the area who had also had client dogs come down with it after that dog show. So he suspected it right away.



I noticed it and got Riker to the vet right away because the illness struck me 'funny.' It was different enough that I didn't think it was a respiratory disease I was familiar with.



Interestingly enough, Bashir - the only other dog I had in the household at the time - never came down with it. Hopefully, though, he was exposed enough to develop immunities.

[Mary]

Our shelter was infected with CIV several years ago after we pulled puppies out of a shelter in Miami FL. Within days we had 20 deathly sick dogs. We wound up losing 2 dogs to pneumonia, and the vet bills nearly bankrupted us; we quarantined ourselves for months till it was finally over. In my experience this disease is a killer.

But having said that, IMO research done by parties with a vested interest may not be reliable. This disease is of more concern in situations where dogs are in close contact such as shelters, dog shows and boarding kennels; I don't think it is of major concern to the average pet owner.

I would very much like to read the article in Veterinary Microbiology - is it available online??

[Gina Spadafori]

Note re: Woody and CIV. He caught it at the Houston cluster of dog shows when he was 7 months old. He was one of the first victims outside of Florida, where the disease was discovered in racing greyhounds.



He would not be alive today had not my friend Mary, who co-owns Woody and who brought him from Sweden an 8-week-old puppy, taken him straight to the vet school at Texas A&M, where he spend a couple weeks in ICU. His recovery was many, many weeks in the making, and really, he didn't truly recover for months.



Woody has been healthy every day since, though. I guess what doesn't kill you makes you stronger.

[Joe]

We have a flatcoated retriever and I just had to say how great the photo is of Woody for this article. Glad he's ok. I can see the flat coat eagerness to participate in things in the way he's looking there.

[Mel]

Thanks for writing about this.



I saw firsthand what CIV did at our shelter last summer. It took down a lot of wonderful dogs, mostly the young ones. We had to close for a week to try and get a handle on it. I can't tell you not only how scary this was to staff and volunteers, but also how devastating.



They were trying anything to get control of it. Antibiotics did not seem to help at all. If there is a tested vaccine, then I am all for it in this case.