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Article Re:CPV-2c

erykah1310
February 23rd, 2008, 12:35 PM
I'm not so sure what they are saying here?!?! Its not deadly but it is??
Its an internet hoax but its not?? Dont worry, but worry? To me its very inconclusive, good information, but IMO alot of talking in circles. What do you think?
http://www.sfgate.com/cgi-bin/articl...19/petscol.DTL

Kristin7
February 23rd, 2008, 12:45 PM
All I see is a page that says item not found?

erykah1310
February 23rd, 2008, 12:49 PM
Hmmmm???
I'll try again and copy and paste too...
http://www.sfgate.com/cgi-bin/article.cgi?f=/g/a/2008/02/19/petscol.DTL

If you've read a dog-related e-mail list, Internet forum or blog in the last week, or spent any time in a dog training class, dog park or at a dog show, you've probably heard about a deadly new strain of canine parvovirus that's sweeping the United States. People say it's not only deadlier than regular canine parvovirus, but that the existing vaccines don't protect against it.
These warnings all cite a press release from Oklahoma State University and the Oklahoma Animal Disease Diagnostic Laboratory as their source, and most of them include a link to that release to back them up. This isn't, they seem to be saying, your usual unsubstantiated Internet rumor, spread without checking by some digital Paul Revere of the dog world. No, they're saying this is true, it's here, it's bad and it's something you and your dogs need to be worried about.

So, is any of this canine doomsday scenario true?

There is a little nugget of reality hiding in there, but the rest of it is a combination of fabrication, misinterpretation and exaggeration, with a dollop of hysteria on top.

Let's start with whether or not this virus is really new, or even newly emerging in the United States. Are American dogs facing some sort of canine Andromeda strain?

For those not in the canine know or too young to remember a world before parvo, canine parvovirus, or CPV-2, first emerged in the world in the late 1970s. It was a truly new virus, recently evolved from the feline panleukopenia virus, although researchers don't know exactly how that occurred. It causes massive diarrhea and vomiting, damages the intestinal lining and in very young puppies attacks the cells of the heart. It also causes depressed white cell counts (leukopenia), one of the main things that differentiate CPV-2 from other forms of intestinal disease in dogs.

When this virus first appeared, no dogs of any age had immunity to it. It swept through kennels and households all over the world, sometimes killing dogs in a few hours.

Today, the situation is completely different. A very effective vaccine exists and CPV-2 disease in vaccinated adult dogs is rare. So when dog owners heard that a new strain of CPV-2 might have emerged that could evade the protection of existing vaccines, many feared a return to the terrible days of the '70s, when CPV-2 was new and deaths were frequent.

Although it's been those spreading the rumors rather than the press release itself that made this claim, it's not hard to see where they got the idea. The press released announced the identification of a new strain of CPV-2 known as CPV-2c. It then went on to say that the Oklahoma Animal Disease Diagnostic Laboratory had received a CPV-2c case where "the adult dog had been vaccinated multiple times and still became sick with Parvovirus," notable, they said, because "normally parvovirus does not affect adult dogs, only puppies."

But while it's true that adult dogs rarely get parvo, that's not because they can't get it, as the experiences of the '70s clearly showed. It's because nearly all adult dogs have been successfully vaccinated for the disease. And while the story of a dog who had been vaccinated multiple times but contracted the disease anyway is very frightening to contemplate, the fact is this is a problem that, although rare, has long been known in veterinary medicine. There is a very small number of dogs, known as non-responders, who are not able to form immunity to CPV-2 even when vaccinated. Although it's easy to infer from the press release that the reason the dog's vaccines failed to protect him was because he was infected with the new strain of parvo, there's no evidence that's the case. Vaccinated non-responders, just like unvaccinated adult dogs, get parvo from the older strains, too.

The rumor mill doesn't just say that the virus is newly emerging in this country, spreading rapidly and has no vaccine; the warnings also tell dog owners that the symptoms caused by CPV-2c are even more deadly than the parvo we already know and fear. People point to statements in the press release such as "Mortality has been quite heavy" and "this particular variant can attack the heart and intestines." Although the press release doesn't blame it on CPV-2c, it does mention 600 puppies who died "in one night," a terrifying scenario right out of any dog lover's nightmares.

But the fact that puppies can die from parvo is not news. That's because immunity to CPV-2 doesn't always form in puppies until 16 or even 20 weeks of age; vaccines given prior to that can fail to work due to interference from the immunity the puppies got from their mothers at birth. This is true of all strains of parvo, not just CPV-2c. And all strains of CPV-2 attack the intestines in all dogs, as well as the heart in young dogs, so that wasn't news, either. The press release sounded dire, but what was really going on?

I contacted Melissa Kennedy, D.V.M., Ph.D., a specialist in microbiology at the University of Tennessee College of Veterinary Medicine and an infectious disease and immunology consultant for the Veterinary Information Network. I asked her what the story was. Is CPV-2c a huge new risk to America's dogs, against which there's no vaccine? Is the sky falling, as everyone at my local dog park assured me?

"Relax, don't panic, don't stay home from work with your dog," she responded. "This is completely different from the emergence of CPV-2 in 1978. Then, we were seeing a truly new virus in dogs, and the population had no immunity. Thus, we saw tremendous amounts of disease and high mortality in both adults and pups. This new strain of CPV does bear monitoring, and eventual inclusion in vaccines will likely occur, but a repeat of the scenes from the late '70s and early '80s is not what we are facing. Concern and monitoring, but not fear and hysteria."

Do current vaccines protect against CPV-2c? All indications are that yes, they do. Kennedy told me that parvo in dogs simply hasn't changed enough since its emergence 30 years ago that immunity to one strain doesn't also confer immunity to the others.

She referred me to a 2006 paper by Dr. Uwe Truyen, the researcher she calls the "guru of canine parvovirus," entitled "Evolution of canine parvovirus A need for new vaccines?" In it, he concluded that the changes that had occurred in the canine parvovirus were too minor to impact immunity in adult dogs. "In the parvovirus system, the changes within the capsid protein that occurred over the last 30 years appear minute," he wrote.

Although adult dogs don't seem to face any greater risk from the new strain than from the older ones, there may be one group that is at increased risk. Very young puppies rely on their mother's antibodies to protect them from disease before they have the ability to form their own. If the mother has antibodies to the older strains, those antibodies may possibly be less effective against CPV-2c.

"My biggest concern is puppies who are totally dependent on the antibodies that they got from their mom to protect them, and in that case they don't have any backup," said Kennedy. "Adult dogs have not only antibodies but cell-mediated immunity, which can help protect them." A number of researchers, including Dr. Truyen, have noted the need for studies examining maternal antibodies and CPV-2c.

In the meantime, what should breeders and those with very young puppies do? Exactly what they should be doing about any strain of CPV-2. "Vaccinate puppies through 16-20 weeks of age. This may vary with the specific vaccine; follow your vet's recommendations for vaccine protocol," Kennedy said. "Avoid mingling pups with other dogs, or even taking them to environments where other dogs have been, like parks, until 16-20 weeks of age."

What about fears that this disease causes even worse symptoms than the older strains of parvo? Is that true? "The current indications are no, that it is a similar disease progression to existing strains," she said. Which isn't to say that owners shouldn't protect their dogs against canine parvovirus. "It's a terrible disease," she warned all strains, not just CPV-2c.

There is one definite concern about the new strain for owners of dogs of any age, said Kennedy, but it doesn't have anything to do with prevention. It has to do with a diagnostic test for canine parvovirus known as an ELISA test.

"Most of the (test) kits pick up the virus in the fecal sample by using an antibody to capture it, to pull it out of the poop," she said. If antibodies are a hook, little particles of a virus known as "epitopes" are the eye that the hook catches. Even though the virus hasn't changed enough that it can elude the immunity to other strains, if it changed in that one epitope, the antibody won't "catch" on the virus, and the test will give a false negative.

"We have seen, in a couple of cases, these anecdotal reports from veterinarians saying, 'Look, the ELISA's negative but this looks like parvo,'" Kennedy told me. "And I tell them, 'Send me a sample.' And we test it by these other methods, like electron microscopy, where we take the feces and actually look at it under an electron microscope and look for parvo. It doesn't matter if it's 2b, 2c, or you know, elephant parvo, we could see it. So that test works." Another test, known as a PCR, is also able to detect the new strain of parvovirus, and Kennedy has seen some cases in her lab that were negative on the in-house test run by the dog's vet, but positive when she used other methods.

What's the takeaway message for dog owners? Certainly not that the sky is falling. While it's a good thing that researchers have an eye on the evolution of all viruses that cause disease, including CPV-2, so far it hasn't changed much. Your adult dog's vaccines still protect him from it, and it doesn't seem to have become more deadly or a greater threat, except possibly to some very young puppies. Veterinarians and dog owners also need to be aware that some fecal tests might give a false negative if the dog is infected with the new strain, although treatment is otherwise the same as for older forms of the disease.

Now, spread the word at the dog parks and on the Internet.

A complete transcript of Christie Keith's interview with Dr. Kennedy is available at Pet Connection.

Christie Keith is a contributing editor for Universal Press Syndicate's Pet Connection and past director of the Pet Care Forum on America Online. She lives in San Francisco.

rainbow
February 23rd, 2008, 01:03 PM
Perhaps this will make you feel better....

http://www.petconnection.com/blog/2008/02/08/parvo/

erykah1310
February 23rd, 2008, 01:09 PM
Thanks Rainbow... I just skimmed through it quickly but plan on reading it further.
So the article is intentionally full of unanswered questions to keep the panic going is the main point I picked up.
Guess its good for vaccination sales vs titers then?!?!

Gotta love the internet...

erykah1310
February 23rd, 2008, 01:27 PM
So...
Christine Keith, a "Petconnection team member" is also the writer of the article which confused me in the first place?!?!

I need to get off the computer for a while, nothing is making sense anymore.
lol

rainbow
February 23rd, 2008, 01:48 PM
Hee hee....yep. :D You can leave a comment on the website I posted or they also have a "contact" link. :D

hazelrunpack
February 23rd, 2008, 08:25 PM
I think she was posing the questions as a means to get the answers out, erykah. Those were the questions she most often heard from concerned owners and she repeated them so she could address them. At least, that's how I read it. :shrug:

Still disturbing, though.

So now we have something else to worry about, but not to worry too much about. :rolleyes: Sigh...

erykah1310
February 23rd, 2008, 08:32 PM
I know Hazel... its inconclusive to me...

Im not in a mass panic over this, I cant say I ever really was. But this article sorta made me go ... "Hmmm?"

Oh well

hazelrunpack
February 23rd, 2008, 08:43 PM
They say that having pets is good for your blood pressure, but with news like this, I can't say as it's helping mine much! :laughing: