spiceofbroadway: (Bella - All About Pets)
It's going to be a bit of a challenge to write up my notes--the seminar tended to jump from topic to topic, especially when people were asking a lot of questions--but I'll give it my best shot.

According to Dr. Dodds, yearly vaccinations were originally recommended for dogs and cats not because there was evidence that they needed them that often, but because it was a mechanism to get pets into the vet's office for an annual check-up. When you compare the number of vaccinations that a dog typically gets in its relatively short lifetime to the number of vaccinations that a person gets in their much longer lifetime--well, it's a bit ridiculous, really. The core vaccinations for dogs (the ones every dog should have) are distemper, adenovirus 2, parvovirus, and rabies. The core vaccinations for cats are feline parvovirus, herpes virus, calicvirus, and rabies. As I mentioned in my last post, I'm not sure what adenovirus is, never mind the what the difference is between adenovirus 1 and 2. I know that Lucy was vaccinated for feline leukemia when she went from being an indoor to an outdoor cat, but I don't know why that's not one of the core vaccinations.

For dogs, parvovirus is the most serious and common disease right now. There have been a number of parvo outbreaks in the U.S. in recent years. There's not much distemper around in the pet population anymore, because of vaccination programs, but it still exists in wildlife and feral dogs and can enter the pet population through contact with those animals. As I mentioned yesterday, there's very little rabies in Ontario. There's no difference between the one-year and three-year rabies vaccine except for the label on the bottle, so dogs don't need to be vaccinated for rabies annually. The goal of Dr. Dodds' rabies challenge study is to evaulate the duration of rabies immunity conferred by the vaccine. She thinks it lasts for seven years or more, perhaps even the lifetime of the dog. When vaccinating your dog for rabies, ask for a vaccine that doesn't have mercury or thimerosal in it (Imrab makes this kind of vaccine).

Another serious illness that dogs can contract is canine influenza, and there is no vaccine for it. Its symptoms look a lot like kennel cough, which isn't life threatening. The difference is that canine influenza comes with a fever, while kennel cough doesn't. If your dog starts to cough and is running a fever, it should be taken to the vet and started on a course of antibiotics immediately as the risk of pneumonia is very high.

The optimal age for vaccinating is 12+ weeks for puppies and 10 weeks for kittens. The earliest safe age to vaccinate puppies and kittens is six weeks, but Dr. Dodds said that vaccinations really shouldn't be given before eight weeks. The age at which vaccinations are effective depends on when the maternal antibodies wear off--if maternal antibodies are still present when a puppy is vaccinated, the antibodies will neutralize the vaccine. This is why puppies get a series of vaccinations: because it's difficult to predict when the maternal antibodies will wear off, and there may be differences between individual dogs and between breeds. Dr. Dodds prefers single vaccinations to combinations, and she recommends giving them 3-4 weeks apart. Again, the most important one is parvo, so it should be given first. Females shouldn't be vaccinated just before becoming pregnant in order to increase antibodies in the pups, because their hormones are out of whack when they're in season, and this raises the risk of adverse reactions. Dogs shouldn't be vaccinated at all after 10 years of age.

It's considered safe to take puppies out into the world three days after their second vaccination. The problem, of course, is how to socialize a puppy while not exposing it to life-threatening viruses when it's still vulnerable, particularly if you're spacing individual vaccines 3-4 weeks apart. Dr. Dodds suggested taking puppies to public places where dogs aren't common, such as parking lots outside of stores and malls, or inviting healthy dogs to your home. Carrying the puppy and having people play with it in your (or their) arms instead of letting it touch the ground in public places will also reduce the risk of exposure. Puppies can attend puppy obedience classes after their first round of shots because owners who take their puppies to classes are generally a clean and responsible lot, so the risk of infection is relatively low. However, there is still a risk, because nothing is risk free, so puppy owners should have this explained to them.

The only vaccination required by law in Ontario is rabies--everything else is a recommendation and is optional. Vets incur no legal liability by not recommending vaccinations, except for rabies, because everything on the label is a recommendation. Ontario law doesn't clearly specify a minimum age at which puppies should be vaccinated for rabies--it says something like "three months or older," which may be interpreted by individual public health officers either as "it must be given at three months of age" or "it must be given sometime after three months of age."

A titre measures the immunity conferred by vaccinations and by natural exposure. Because of the lower limits of lab tests, any measurable titre is considered protective--a measurable level = committed immune memory cells. The number provided on a titre test (e.g., 1:256) refers to the number of dilutions it took before antibodies could no longer be detected. A higher second number in the ratio (1:1024) is better than a lower number (1:16), but any measurable titre is a good titre. However, in Ontario, public health officers will not accept titres as evidence of vaccination.

After vaccination, a dog's titre will rise for about three months, after which time it will stabilize and return to the dog's basal level. Once the animal has stabilized, its titre should stay at its basal level and not decrease with time. This is only true for virus vaccinations, not bacteria vaccinations (such as lepto), but I don't know why. This is why Dr. Dodds doesn't think that dogs need to be repeatedly vaccinated against viral diseases. You can't boost an immune system that is already on guard for a specific disease, and over-vaccination can backfire and weaken a dog's immune system. [On a human note, annual flu shots are recommended for susceptible individuals because cold and flu viruses mutate quickly--this year's flu is not the same as last year's flu, and immunity to one doesn't provide immunity to another. That's why you can catch colds and the flu throughout your life. I don't know why these viruses mutate quickly while other don't.] Titres should be done several months after vaccinating (so that you're not measuring the temporary spike) and then again in several years.

Inoculated dogs will shed virus, so dogs that come into contact with them may show a measurable titre even if they haven't been vaccinated themselves. Dogs can also be exposed to a virus in the environment without necessarily becoming sick, so they can produce positive titres that way too. Rabies is always fatal, however, so a dog can only produce a measurable rabies titre through vaccination. I'm a little fuzzy on why rabies virus can't be shed by vaccinated dogs--I'm guessing it's because the the rabies vaccine is a killed virus rather than a modified live virus. A modified live virus will reproduce in the dog's body, but a killed one won't. In any event, Dr. Dodds was quite clear on this point: positive rabies titres can only be gained by vaccination. She has had the occasional positive titre from an unvaccinated dog come up, but it's always been a false positive as a result of a clerical error.

The rabies vaccination is the strongest vaccination given to dogs, and it's one of the ones most likely to cause adverse effects. Rabies vaccinations should be given separately (i.e., 3-4 weeks before or after) from other vaccinations when the dog is healthy, not in heat, etc. Dogs with chronic conditions (e.g., hypothyroidism) shouldn't be vaccinated at all. A letter of exemption from a vet is acceptable in lieu of a rabies vaccination in Ontario, so owners of geriatric dogs (> 10 years old) or dogs with chronic health problems should get one of these from their vet. Adverse reactions from the rabies vaccination can include changes in temperament.

To be continued...

~*~

Bella's right eye was kind of runny yesterday evening, and the white part of her eye was an interesting shade of pink. I made an appointment with the vet for this afternoon. The vet examined Bella's eye, said her cornea appeared to be clear and unscratched, noted that the accumulated goop (which I hadn't wiped off because I wanted her to see it) was slightly green and the tissues around her eye were a little swollen, and concluded that it was conjunctivitis. I have cream to put in both eyes to clear it up/prevent the other one from becoming infected. Bella's eye looks a little more gooey than usual, but it doesn't seem to be causing her any discomfort and she's not squinting or blinking any more than normal. She sure doesn't like having the cream put in, though. But, then, neither would I. And she can't go to doggy daycare tomorrow because she might be contagious. :-(

While I was at the vet's, I also had a Lyme test done to see if that's what made her sick in July. It came back negative (she was also negative for heartworm--they do both at once). I talked to the vet about whether her illness could have been a reaction to the vaccination, but she was inclined to say no until I mentioned that Bella had been having a false pregnancy at the time of the vaccination (it was a different vet than the one who told me about the false pregnancy). Then she conceded that it might have been. Since parvo is an immunosuppressive virus, it might also have been the start of an opportunistic infection that moved in while her immune system was below par after the parvo vaccination. There's no way to know. I think I'll bring Bella in for titres--including a rabies titre--after her next heat. If the rabies titre comes back positive, then I'll ask if they'll sign a waiver for rabies shots on the condition that I have rabies titres done every three years. I'm also going to email Jean Dodds and ask her opinion. Mairon has emailed her a few times, and she said that she's always gotten an answer.
spiceofbroadway: (Dogmom - eyesthatslay)
Went to Jean Dodds seminar yesterday. Information overload. Head exploding. Oy.

She talked about three main topics: vaccinations, nutrition, and hypothyroidism. The audience asked a LOT of questions, so although I took copious notes, they don't exactly follow a linear progression. I will attempt to summarize them in installments in the next week or so.

There were two main points of interest for me: leptospirosis vaccinations and vaccinosis. I should qualify that--it was all interesting, but those two things were ones that were on my mind going in and coming out.

Regarding lepto, Dr. Dodds said that she would never vaccinate for it unless there was a huge local outbreak that had been shown to be caused by one of the serovars included in the vaccine. She thinks that the risk of an adverse reaction is just too high and the benefits too low. She acknowledged that lepto is a very serious disease that can be passed from dogs to humans. She said there were two strategies for dealing with it in areas (such as Peterborough) where it is endemic: vaccinate and hope for the best, or don't vaccinate and whisk your dog into the vet's at the first sign that something's off. If symptoms suggest that it might be lepto, then the dog should be started on a course of doxycillin or amoxicillin immediately, and a test for lepto should be performed. There's no way to confirm a lepto diagnosis quickly, so you have to treat in the absence of a diagnosis. That pretty much sums up what happened when Bella got sick this summer: I had her at the vet's within an hour of coming home and finding her acting "not right," and the vet started her on amoxicillin the next morning after Bella's fever had risen overnight. As it turned out, Bella didn't have lepto, but it's comforting to know that the vet and I both responded appropriately.

During lunch, I told the people at my table about Jilly's terrible reaction to Fort Dodge's lepto vaccine a number of years ago. A couple of people mentioned that Fort Dodge had admitted to batches of contaminated lepto vaccines that made a lot of dogs sick. After they'd mentioned that, I remembered that Jilly's vet bills were paid for by Fort Dodge, so she was almost certainly one of the dogs who got the bad vaccines. I'm pretty sure Linus got the lepto vaccine that year too (but never again)--I guess it was either stunning hybrid vigour or luck of the draw that he didn't get sick.

Regarding vaccinosis, Dr. Dodds wasn't entirely clear on whether individual vaccines were preferable to multiple vaccines. At one point, she did say that individual vaccines should be given several weeks apart, but she also referred to parvo/distemper/adenovirus vaccine combos without saying anything negative about them. (On a side note, I'm not even sure what adenovirus is. It's one of the four "core" vaccines that she thinks every dog should get, but I've never actually heard of it before. Linus got annual "combo-wombo" vaccinations (except for lepto, except that one year), so presumably it was in his mix, but Bella's never had it as far as I know.)

One way or the other, several things can increase the risk of vaccinosis: genetics, stress, sex hormones, poor nutrition, and existing health problems. Breeds with dilute coat colours are more prone to adverse vaccine reactions. Dr. Dodds didn't mention Tollers specifically here, but she did say that dogs with lighter coat colours and pink noses were in this group. Females shouldn't be vaccinated when they're in heat, in the 30-day period before estrus, while pregnant, or while lactating. Males shouldn't be vaccinated around times of breeding or if they're housed with females who are in heat. Adverse vaccine reactions typically happen within 3-10 days following vaccination, although they can show up as late as 45-60 days. (I would have liked to have seen a list of possible reactions, but there were so many questions being asked by the audience that she wasn't showing her slides methodically here.) Additionally, parvovirus and retroviruses are immunosuppressive viruses. Therefore, parvo vaccinations will suppress the immune system for several days. Thus, if you vaccinate puppies for parvo and there is "street parvo" in their environment, they may come down with parvo. They don't get parvo from the vaccination, but the street parvo can move in and make them sick during the period of immune suppression before immunity kicks in. Finally, if a dog has a vaccine reaction, that dog should not receive any more vaccinations, ever, including rabies.

Speaking of rabies, and I did not know this, the current protocol for dogs is to get their first rabies shot sometime in their first year, to get a booster one year later (regardless of the fact that current vaccines are three-year vaccines), and then to get rabies shots as required by law (generally, every three years) thereafter. Dr. Dodds has begun a rabies challenge study to determine how long rabies immunity really lasts, but she said at least twice that rabies should be given at < 1 year and again one year later. (The one-year booster is the part I didn't know about.)

So.

Bella was vaccinated against rabies a couple of days before she flew from Minneapolis to Toronto. She didn't have any adverse reactions to this shot, as far as I know. She was very shy for the first couple of months in Peterborough, but I think that was far more likely to have been the result of the huge change in her lifestyle and environment, not to mention the flight itself, than an adverse vaccine reaction. That was her first rabies vaccination; according to Jean Dodds, she should have another in December 2008.

Bella was given a parvo/distemper (only) vaccination on July 4 (it was specially ordered in for her). We also discovered that day that she was having a false pregnancy. On July 10, I came home and discovered that she was getting sick. She was running a low fever and was lethargic, but she didn't have any other symptoms at first. Her fever was higher on July 11, as was her white blood cell count, and she was stiff, sore, and having problems getting to her feet after lying down. She also had difficulty going up stairs or even getting into the car. She was started on a course of amoxicillin and showed significant improvement within 24 hours, as is often the case when an infection is treated with antibiotics.

Tollers are one of the breeds that are predisposed to vaccinosis, so Bella had genetics working against her. She shouldn't have been vaccinated during a false pregnancy, but I didn't think of that until a day or two later, so she had that working against her too. She wasn't particularly stressed--all dogs get a little edgy when they go to the vet's, but Bella was pretty relaxed about it all. She has a high-quality raw diet and is generally in great health.

So why did she get sick? Was it vaccinosis? It could have been--it was in the right time frame. She was vaccinated during a false pregnancy, which is a no-no, and that increased her risk of reaction. All the tests they ran came back negative, and her final diagnosis was "fever of unknown origin," which isn't a diagnosis at all. And, in fact, vaccinosis is usually a diagnosis of exclusion.

Did she get sick because there was something in the environment that took advantage of the period when her immune system was suppressed? That's possible too--the time frame was also right for that, and she seemed to respond to the antibiotics in the way that infections typically do. Amoxicillin is a broad-spectrum antibiotic, so even though an infection was never found, Bella could have had something starting somewhere that was quickly knocked out by the drug.

But what if it was vaccinosis? If that's the case, then she shouldn't be vaccinated ever again for anything, including rabies. Which, because Cathy and I agreed to follow Jean Dodds' protocol, is the only vaccination she has left, and she's due for another one in December. And rabies happens to be the strongest vaccination out there--it's known to cause a lot of vaccinosis.

Except for bat-strain rabies (and the incidence of rabies in bats is very low), there is no rabies in the Peterborough area. An aggressive anti-rabies initiative by the provincial government has wiped it out in this part of Ontario and limited its entry from New York state to small areas around Wolfe Island and Niagara Falls. Rabies vaccinations are required by law in Ontario, but you can get a waiver from a vet if your pet has had an adverse vaccine reaction in the past (this is what Jilly has).

I discussed all this with the people at my table at lunch, and they agreed it was a tough call. There's really no way to know why Bella got sick in July. If it was an opportunistic infection, then it's okay to vaccinate her for rabies. If it was vaccinosis, then she shouldn't be vaccinated anymore, period. I was sitting next to a Golden Retriever breeder who believes in minimal vaccinations, and her opinion was that Bella shouldn't get any more rabies shots. I don't know if I could convince my vet to write a waiver for me or not. She might do it if I agreed to annual rabies titres.

I think I need to email Dr. Dodds.

~*~

I met and talked briefly with Shannon Viljasoo and Mairon Bennett before the seminar started (they were sitting two tables away from me), and then met up with them and Chris Choi in the parking lot afterwards. Chris looked quite delighted to see me and gave me a hug :-). For the most part, I've found Toller people to be friendly and helpful, but sometimes I detect an undercurrent of bias against newbies to the breed, so it meant a lot to me to have Chris do that. I've emailed Shannon a fair bit (and Mairon, but much less), so it was great to meet them in person. The four of us made for an odd kind of symmetry: Shannon, Chris, and I have the only three Maverick pups in Ontario, while Shannon, Chris, and Mairon are owners of dogs from the near-legendary Onepenny Pipercub litter (Mairon was the breeder, of course). I need a Onepenny Toller and Mairon needs a Maverick pup, and the circle will be complete. :-) There's a specialty fundraiser in Bowmanville in October, so I'll go to that and get to hang out with them some more. We'll all also be at the the Toller booster/AGM in Orangeville in December, so I'm looking forward to that too.
spiceofbroadway: (Default)
I work for the Ontario government at the Ministry of Natural Resources. MNR is the ministry that tracks rabies, and it runs a pretty aggressive rabies eradication program (vaccine-filled baits, distributed by airplanes, are used to vaccinate wild animals over a large area). For the curious, it's worked pretty well in controlling the fox and raccoon strains of rabies in Ontario. It doesn't work so well with bats since they eat insects in the air, not bait on the ground.

I thought I read on one email list or another that MNR also tracked leptospirosis, which was news to me. As this is the disease that has been most on my mind lately, I figured I'd look into it. I sent out enquiring emails from my work account, got passed around a fair bit, and finally learned that lepto is not tracked in Ontario.

My email eventually got forwarded to Dr. John Prescott at the University of Guelph, a vet who researches lepto, among other things. I have a pretty broad scientific background, but it unfortunately does not include things like immunology and whatnot. So although Dr. Prescott did his best to answer my questions, I confess that I don't fully understand what he wrote. Still, I will put it here for the record and so that I can reference it later on.

He wrote his answers to my questions in all caps, which I find hard on the eyes, but I'm not going to retype everything he wrote just to change it to lower case.

~*~

Kristina: I know that lepto vaccines for dogs cover only four lepto serovars, and I've read that there are many more serovars than this, some of which are on the rise in Ontario.

Dr. P: THE VACCINE COVERS THE GREAT MAJORITY OF THE SEROVARS THAT CAUSE DISEASE IN DOGS, BUT DOES NOT HOWEVER INCLUDE BRATISLAVA, WHICH MAY CAUSE SPORADIC CASES IN DOGS. IT DOES NOT INCLUDE HARDJO, WHICH S A CATTLE/SHEEP SEROVAR THAT DOESN'T SEEM TO CAUSE CANINE LEPTO.

ONE QUESTION ABOUT THE VACCINE RAISED IS WHY IT DOESN'T INCLUDE AUTUMNALIS. IT SEEMS THAT THE "AUTUMNALIS-REACTING" DOGS ARE PART OF THE VERY BROAD CROSS-REACTIVITY AND HYPERAGGLUTINATING NATURE OF AUTUMNALIS. I DON'T BELIEVE THAT AUTUMNALIS OCCURS IN ONTARIO.

Kristina: I'm interested in finding out how many cases of diagnosed lepto are caused by the serovars covered by the vaccine and how many are caused by the others.

Dr. P: IMPOSSIBLE TO SAY BASED ON OUR CURRENT DIAGNOSTIC APPROACHES, THAT ARE LARGELY SEROLOGICAL, BUT I THINK THAT 95% OR MORE OF CANINE LEPTO ARE CAUSED BY SEROVARS IN THE VACICNE, SPECIFICALLY GRIPPOTYPHOSA AND THEN POMONA.

Kristina: I'm particularly interested in the Peterborough/Bancroft area, but I know many folks who would be interested in this sort of information from anywhere in Ontario (or even Canada, for that matter). Does the University of Guelph collect data of this sort? (MNR apparently does not.) If yes, has it been published or is it shareable?

Dr. P: AGAIN, IMPOSSIBLE TO SAY BASED ON SEROLOGY AND THE CROSS-REACTIVITY OF EARLY CANINE LEPTO SERA BECAUSE OF IgM CROSS-REACTIVITY, BUT PETERBOROUGH AREA HAS BEEN WHERE WE HAVE SEEN HYPERACUTE LEPTO IN DOGS. I DON'T KNOW WHETHER THIS IS BECAUSE OF SOME LEPTO-AWARE VETS IN THE AREA (THIS IS PART OF IT) OR WHETHER THERE'S MORE RACCOON AND SKUNK INTERACTION OF DOGS IN THE AREA. OTHER PEOPLE HAVE THOUGHT IN THE PAST POSTULATED THAT CANADIAN SHIELD PROMOTES LEPTO BECAUSE OF ALKALINE?? NATURE OF THE SOIL ALLOWING GREATER SURVIVAL OF THE ORGANISM IN THE ENVIRONMENT ONCE IT'S SHED BY THE CARRIERS IN THEIR URINE. THIS WAS BARBARA KINGSCOTE'S THEORY FROM 40+ YEARS AGO.

[Note from Kristina: The Canadian Shield is predominantly granite, which would make the soils acidic, not alkaline. He's a vet, not an environmental chemist.]

HOPE THIS HELPS; LOTS OF QUESTIONS, PRECISE ANSWERS DIFFICULT BECAUSE ONE IS EXTRAPOLATING FROM SEROLOGY AND GENERAL KNOWLEDGE OF LEPTO.

CANINE LEPTOSPIROSIS IS FOUND THROUGHOUT ONTARIO, AND PREVALENCE DOES TO SOME EXTENT REFLECT AWARENESS OF VETERINARIANS.

~*~

Not understanding all of that, I sent him a second message for clarification:

Kristina: Thanks so much for your message. My questions come from both professional and personal interest. I work for MNR, and I know that rabies is tracked here. I was wondering if lepto was as well, since it can be transmitted to humans, but apparently it's not. Do you know if there are many cases of people contracting lepto from their infected pets? In your opinion, do you think it should be tracked?

I THINK LEPTO IN DOGS SHOULD BE REPORTABLE BECAUSE OF THE HUMAN RISK

LOOK UP CANADIAN MEDICAL ASSOCATION JOURNAL ON LINE FREE

Prescott, J. F. 2008. Canine leptospirosis in Canada: A veterinarian's perspective. Can Med Assoc J 178:397-398.

Brown, K., Prescott, J. F. 2008. Leptospirosis in the family dog: A public health perspective. Can Med Assoc J 178: 399-401.


Kristina: The personal interest side comes from being an owner of a Nova Scotia duck tolling retriever. Tollers seem to experience more autoimmune disorders and adverse reactions to vaccinations than other breeds, so many Toller breeders recommend a limited vaccination protocol that doesn't include lepto. Lepto vaccines have a reputation (at least, within the Toller community) for causing more adverse reactions than most other vaccines, and they only provide immunity for several months and must be repeated annually, so it's regarded as not worth the risk. My mother's dog, a Sheltie/Corgi mix, had a terrible autoimmune reaction to Fort Dodge's lepto vaccine when it first came out several years ago and now can't be vaccinated against anything at all. (Fortunately, she's a fairly inactive older dog, and the thing she's most likely to pick up is a case of frostbite in winter.)

Dr. P: TOO BAD, NOT HEARD OF THIS

Kristina: On the other hand, my vet here in Peterborough has had several cases of lepto in the past few years, and I recently heard of a Toller in this area who died from leptospirosis.

Dr. P: RIGHT, PETERBOROUGH MAY BE HOT

Kristina: What is "hyperacute lepto" in dogs?

Dr. P: DIE IN ONE DAY OF SEPTIC SHOCK

~*~


Die in one day of septic shock? Gah! How am I supposed to weigh that against Jilly's very bad autoimmune reaction to Fort Dodge's vaccine?

Increased interaction between raccoons and dogs in this area? You could say that. We came home from the cottage one weekend last fall to discover five raccoons on our roof. Jim climbed up there and knocked one off with a shovel. The others fled.

I wonder if I can convince Jim to move out of the Peterborough area? To Mars, maybe. I bet there's no lepto at all on Mars! :-/

I guess my next step is to read the two papers he referred to (and hope I can understand them), and then call some local vets to find out how many cases of lepto they've actually seen and what the outcomes were. I'll also talk to Liz about it on Sunday. She lives in Bobcaygeon, which isn't far from Peterborough, and has lots of dogs in the field. I'm pretty sure she doesn't vaccinate against lepto.

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