Emerging Diseases and Zoonoses Series #14–Dog flu strikes Wyoming

Cheyenne shelter dogs to be euthanized

All 70 to 80 dogs at the Cheyenne Animal Shelter will be euthanized because of an outbreak of canine influenza that has closed the shelter for more than two weeks, shelter officials announced.

Shelter officials said there was no way to test for the virus quickly and thus no way to tell which dogs were infected. Shelter director Alan Cohen said that unless all the dogs were killed, he couldn’t guarantee that they wouldn’t re-infect themselves and other animals.

“If I do not euthanize these animals, how can I let them loose knowing they might spread it to the community? If we don’t stop these 70, they may serve as vectors to spread it to the entire community,” he said.

The virus has also been turning up in dogs around town. As of Monday, Frontier Animal Clinic had confirmed three cases, including one dog that died rapidly, according to clinic veterinarian Gary Norwood.

Norwood urged dog owners to remain calm and take precautions. He said that while the virus has a fatality rate of 3 to 10 percent, most dogs recover or never even show symptoms.

“For 95 percent of cases, the dog’s going to recover just fine,” he said. “People need to not panic. Respect that this virus has entered our community. Use logic. Use hygiene. This virus is susceptible to normal hygiene procedures.”

(Continued below)

As mentioned here, this influenza is a fairly new arrival into the dog population. It’s a serotype H3N8 virus that jumped from horses to dogs, and has mainly affected dogs housed in groups–at racetracks, kennels, shelters, etc., where it can spread through the population quickly.

Can we make any extrapolations from “equine flu” –> “dog flu” with “bird flu” –> “human flu?” Some, I think. It shows how quickly an influenza virus can be established in a new population (especially a crowded population), and the sometimes-drastic measures that need to be taken to prevent further spread. Obviously, we can’t euthanize humans to contain an influenza outbreak, but Norwood’s advice is good whether such an outbreak occurs in dogs, birds, or humans. However, as they note, tough choices may need to be made. It must be horrible for the people working there to be forced to put down all those dogs, but during an epidemic situation, difficult decisions can become commonplace, and people may protest and not understand. (Take a look at all the comments to the article, for example). Immunizations aren’t available for canine influenza, and there’s not a rapid test for the virus that makes it easy for veterinarians to diagnose. These are also potential issues for any novel human influenza virus, whether it’s H5N1 or another viral serotype.

8 Replies to “Emerging Diseases and Zoonoses Series #14–Dog flu strikes Wyoming”

  1. That breaks the heart – I would have a very difficult time killing dogs on that scale – having been raised on a cattle farm, well, the sentiment is not necessarily an extensible property.

    I was listening to a discussion on, I believe, “Talk of the Nation” about the new Federal planning guidelines for a [bird flu] pandemic, with everything from the “3ft. rule” to various ‘cordon sanitaire’ strategies. There was a lot of different skepticism expressed about all sorts of things in the plan, but in particular, two things popped out at me: first, the question of virulence, and second (and I would imagine dependent on the former) the models for transmission.

    The first question was: presumeably, for the virus to jump to the human population it needs to mutate whatever binding sites/receptors are on the virus to match up with human cell binding sites; since the virulence has to be largely affected/determined by precisely that characteristic of the virus, it seems like the virulence itself is somewhat non-determinate. It seems as if it would be possible for a fairly virulent stain in birds/swine/dogs/whatever, to jump to another species and be barely transmissible. Similarly, something innocuous in the original host might be quite virulent in the new species (wasn’t that the case with one of the swine influenza variants – like the ’57 strain?)

    The second was two-fold – how to you model something when you don’t really know the answer to the first question, and then, how do you really predict something with this many possible terms? That is, what’s the solution to the three-body motion problem?

  2. Scott, you’ve hit the nail on the head regarding all the “hype” and wildly different predictions about H5N1. Indeed, right now H5N1 is highly pathogenic and apparently highly transmissible among many bird species–but doesn’t transmit human-to-human efficiently. Some say it never will be able to–I don’t think we know enough about that yet. Predictions based on the information we have are an educated guess–they may be right, but we may be missing a critical factor.

  3. So, in a previous posting, you were discussion the sugars which appear to be the binding sites – how common is this, or are viruses (virii?) your bag? The seed article (I confess I’ve not read the others, so if the answer’s there, just tell me to go read) could be read to suggest that there is a general class of avian viruses which generally bond deep in the lungs, but I may be misreading. Are similar structures there on cells of the upper resperatory tract?

    Sorry to be so pesky.

  4. Sorry – to clarify the question – I realize from the Seed article that the identical structures aren’t there – and that this is the speculated reason for resistance – but I’m wondering if there are similar structures – close enough to make mutation more probable.

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