Lyme Disease

Part three

Now, for the final article looking at Lyme disease.  We will look at prevention, testing and vaccination.  This is perhaps the most difficult to put together because there are so many shades of gray!  A quick note to those of you who live in the northern parts of New England, till quite recently many of us including some vets, felt fairly safe that ticks had not come so far north, perhaps because of the cold winters.  My good friend who lives in Canada about 15 miles north of the border was recently bitten by a tick.  They are here!

In the early spring, most vets avail upon us to have our dogs tested and vaccinated against Lyme disease.  Many dogs test positive for the disease.  How accurate are these tests when it has been shown that less than between 5 and 10% of dogs exposed to Lyme disease actually get it.  There is also a large discrepancy between the number of dogs that test positive for Lyme and those that are actually sick from the disease – so a positive test is only one piece in the puzzle. Let’s take a quick look at some of the tests used.

3DX – this is an in house test relatively inexpensive, does not react to vaccine (no false positives due to vaccinations).  Tests antibody to C6 Burgdorfer protein. (Antibodies are the body’s agents that fight disease) 

Elisa – Indicator of previous exposure OR vaccination.  Does not always determine exposure from vaccination. Most veterinarians consider a fourfold rise in antibody titers diagnostic of the disease. Not definitively diagnostic and reasonably expensive.

Western Blot - This test can differentiate between vaccine and disease exposure.  It can be useful in distinguishing between antibody levels due to infection versus those due to vaccination.  However, this test is subjective and requires human interpretation and is expensive.

Lyme C6 Quantitative Antibody Elisa – (With a name that long it better be good) this test provides excellent interpretive information – provides good guidelines for whether to treat or not. This test is moderately expensive.

In addition to any of the tests above, your vet may require additional diagnostic testing to be done to rule out other infections or diseases. 

Routinely the 3DX is done in the vet’s office and is a good place to start.  If  a dog tests positive but doesn’t manifest any symptoms the treatment options are – don’t treat and watch for symptoms or do further testing such as the Lyme C6 Quantitative Antibody Elisa to determine whether it is a true and active infection or not.  Another treatment option is to vaccinate and treat.  The gold standard in treating Lyme disease, which is very effective, is the antibiotic Doxycycline given in a dose per weight of the dog – twice a day for 28 days. 

Of course the key is prevention, the goal being to prevent tick engorgement, remember a tick has to be feeding on its host for at least 48hours before the disease can be transmitted. Some preventive messages include:

           A topical tick repellent containing DEET or Permethrin

           Tick collars

(Be sure to check with your vet about any negative reactions from these chemicals)

 Daily grooming

 Reduce tick populations by limiting deer, rodent population and keeping grass and brush short     where the dog frequents.

 Vaccination – this is still debated.

It is important to talk with your vet during the course of your dog’s regular check ups, but armed with some knowledge, you may be able to help choose the right course for your dog’s prevention of Lyme disease.

Knowing the most consistent clinical signs of Lyme can help you get your dog to the vet as soon as possible to be diagnosed.  If left too long Lyme can cause heart disease, damage to nervous system and cause kidney disease.

These signs include:

Recurrent lameness in a joint with complete recovery

Reluctance to move (pain)

Swelling in joints and warmth associated with the swelling

Fever

Lethargy

Depression

There have been some cases of aggression associated with Lyme as well as the above.  While the numbers are low, Lyme may be added to the laundry list if a dog suddenly shows aggressive behavior not common to the animal. These signs can also be significant indications of other illnesses and your dog should be seen if any of the above occurs.

This series is a limited look into the mysterious Lyme disease.  Some dogs can get it, others not.  Some can carry it and never show symptoms, others become symptomatic.

I hope there is something here you can take away and use this summer as you and your dogs enjoy the good weather.  Happy tick free tails!