Lepto: Know Your Dog’s Risk!

risks of lepto vaccine

If you’ve ever considered giving your dog the lepto vaccine (or if you know somebody who does), please read and share this important information.

I’m going to tell you why the lepto vaccine is a terrible idea …

… even when the number of dogs getting lepto these days seems to be on the rise.

Getting Real Answers

Lepto is spread by the Leptospira bacteria, which is transmitted in the urine of infected animals – which are typically rodents. Rats are the most common carriers, but raccoons, opossums, dogs, and even pigs, cattle and horses can carry it. The infected urine runs into the soil and water, where it can survive for weeks or even months.

When dogs drink contaminated water … or if they swim in the water and have a cut or wound – then they can be at risk for lepto. And the bad news is, if your dog is infected, he can pass the infection on to you!

But before you run out and get that vaccine, let’s take a look at just how likely your dog is to get lepto in the first place. The lepto vaccine is one of the most dangerous vaccines your dog can get, so we should really be sure he needs it before we give it to him.

Once you vaccinate your dog for lepto and he suffers a reaction, you can never reverse that decision or the damage … so let’s objectively look at whether the vaccine makes sense for your dog or not.

But first, let’s discuss what lepto is and how it can harm your dog.

Symptoms Of Lepto Infection

The clinical signs of lepto infection will really depend on the health and age of your dog.

The symptoms typically appear 4 to 12 days after exposure and can include fever, muscle pain, vomiting, diarrhea, lack of appetite, lethargy and blood in the urine.

Lepto primarily affects the kidneys and liver, so more serious cases can result in jaundice (yellowing of the skin and the whites of the eyes). Jaundice is a sign that the liver is inflamed (this is called hepatitis).

What Are Your Dog’s Chances Of Getting Lepto?

I really wanted to have a good answer for that, so I did some research. What I found was a nice little study that took blood samples from over 33,000 dogs to see what the rate of lepto was in the US. Perfect!

The results were worrisome!

In fact, the vaccine manufacturer Duramune used these results to prove that we should all run out and vaccinate our dogs (preferably with their vaccine).

They said the risk of lepto was big and they were right … because this study showed that 8% of the dogs tested showed antibodies to lepto.

But they really, really want you to buy their vaccines, so  they might have jumped the gun a bit. Because there are a few things they didn’t mention …

Most Lepto Infections In Dogs Are Subclinical

Once your dog is exposed to lepto, it’s important to realize it doesn’t mean he will get sick.

In fact, many dogs show no symptoms at all.

For those dogs who do show overt symptoms of lepto, fatality rates don’t exceed 10%.

For many owners however, that risk isn’t one worth taking and they want to protect their dog. And that’s understandable …

But let me finish talking about risk and why you might want to hold off on that vaccine.

Many Lepto Infections Aren’t Really Lepto

You read that right … many dogs who are diagnosed with lepto don’t really have it.

And the vaccine has something to do with that.

Once your dog is vaccinated for lepto, diagnostic blood tests will no longer work. So if you bring your sick dog into the vet clinic and they test for lepto … and he’s been vaccinated for it … the test will be positive for lepto, whether he has it or not. The blood tests can’t tell the difference between the antibody in the vaccine and in the real disease.

Let’s Look At The Risk Again

So the scary study said that 8 percent of dogs have antibodies for lepto. But we now know that just because they have antibodies doesn’t mean they’ll be sick. And, even more significantly, many of the dogs in that study would have been previously vaccinated for lepto. Those dogs would have skewed the results and should not have been in the study at all.

This study just asked for results from the labs who tested the bloodworm … they knew nothing about the vaccine history of the dogs (which we now know is really important), and they knew nothing about the dogs (so we don’t know how many dogs were actually sick).

So even if every dog that had antibodies for lepto in that study did in fact have full-fledged lepto, we know the mortality rates are less than 10 percent. So if (and that’s a giant if) those 8 percent of all dogs all got sick, then we can assume that .8 percent of all dogs will die of lepto.

Less than one in a hundred. And if half of those dogs were vaccinated for lepto, then less than one in two hundred dogs in the US die of lepto.

But if it’s your dog who is the casualty, the statistics don’t matter, do they?

But hang on a minute, because …

Serovars Matter

What the vaccine manufacturer failed to mention was that the newer vaccines only protects against four of the over 230 serovars for leptospirosis (the older vaccines only protect against two). These four serovars are:

  • Leptospira canicola
  • Leptospira grippotyphosa
  • Leptospira icterohaemorrhagiae
  • Leptospira pomona
  • Now what’s interesting about the study is the serovars they found to be most commonly found in dogs:

    “Antibodies were most common against serovars Autumnalis, Grippotyphosa, Pomona, and Bratislava.”

    Notice how the vaccine only protects for half of the most common lepto serovars?

    But you still might be saying you still want to go ahead and vaccinate your dog for lepto.

    That’s cool … but do your dog a favor and read this last part before you do.

    Lepto Vaccine Dangers

    It’s important to realize that the lepto vaccine is not a core vaccine. Why is that?

    Well, unlike the core vaccines (like parvo and distemper), many dogs aren’t really at risk for lepto. But it’s also likely because the lepto vaccine

    1. isn’t as effective
    2. doesn’t protect for as long (one year maximum)
    3. and is more dangerous than other vaccines.

    Here’s what The World Small Animal Veterinary Association (WSAVA) has to say about the lepto vaccine:

    Leptospira vaccines provide short-term immunity (e.g., 3–12 months) and the efficacy is often less than 70%. Also leptospira products often prevent clinical disease but fail to protect against infection and shedding of the bacteria, especially when infection occurs more than 6 months after vaccination. The immunity among the serovars varies and immunity varies among vaccinated dogs. Persistence of antibody after vaccination will often be only a few months and immunological memory for protective immunity is short (e.g. 1 year or less). Thus, revaccination may be required as often as every 6–9 months for dogs at high risk.”

    So that means that even if you vaccinate your dog for lepto, he’ll be completely unprotected for up to 9 months of the year.

    And even for the three months your dog is protected, he’s only protected for four of the 230 servovars .. and certainly only for two of the most common four serovars.

    Ultimately, the increasingly small chance of protecting your dog from lepto comes at a cost.

    Not yet convinced? Here’s another reason to avoid the lepto vaccine, from our friend and veterinarian, Dr Patricia Jordan:

    “If your dog is vaccinated for lepto, the antigens in the vaccines do the same harm to the immune system as possibly a natural infection. There have been cases of dogs having to go through dialysis also to save them and no Leptospira were found. The reason? The damage from the antigens in the vaccinations are just as capable as causing the disease pathology!”

    Bet your vet didn’t mention that to you. But wait, there’s more …

    “Vaccinating your dog can also destroy the kidney in 48 hours and in some cases, cause untreatable dermatitis. The damage from lepto vaccination to your dog’s immune system also includes the associated risk of cancer from the adjuvant (chemicals in the vaccine), and the same adjuvant is associated with upregulation of IgE and the consequence includes allergies, asthma, atopy, anaphylaxis and death.”

    Vaccine researcher, Catherine O’Driscoll also found the following interesting relationship:

    “In the 1996 Canine Health Concern vaccine survey 100% of dogs with leptospirosis had been vaccinated within three months prior to infection. This can only be because:

    1. The vaccine caused the disease, or
    2. The vaccine didn’t contain the serovar that caused the illness, or
    3. The vaccine contained a non-local serovar that the dog hadn’t adapted to, or it just didn’t work.”

    So not only is the lepto vaccine riskier than the other vaccines … your vet will want you to give it to your dog more than three times as often as the core vaccines.

    The WSAVA agrees:

    “This product is associated with the greatest number of adverse reactions to any vaccine.

    Still want to vaccinate your dog for lepto?

    If you do, I’ll leave you with this final thought that I pilfered from Judith DeCava’s book, “Vaccination: Examining the Record:”

    A dog not vaccinated has ONE RISK: catching the disease.

    The vaccinated dog has TWO RISKS; catching the disease and damage from the vaccine.

    RELATED: Want to learn the warning signs of lepto and how to treat it with homeopathy? 

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