lyme disease in dogs
In the past, Lyme disease was primarily the concern of dog owners in the northeastern United States, and indeed, the disease is named for the Connecticut town where several cases were discovered in the 1970s. However, in recent years the disease has rapidly spread to affect dogs and people across a much wider area.
What causes Lyme disease in dogs?
The organism that causes Lyme disease is a spiral-shaped bacteria named Borrellia burgdorferi. Ticks pick this organism up from one of their hosts and are able to transmit it to other hosts, including you or your pet. While humans tend to get a characteristic “bull’s-eye” skin lesion around the tick bite, most pets do not.
Generally, Lyme disease tends to affect dogs more so than cats. Cats CAN be infected with the organism that causes Lyme, but they do not seem to develop clinical signs of the disease, nor do they need treatment. (Some dogs fall into this category as well, but more on that in a moment.)
Symptoms of Lyme disease in dogs
It takes as little as 24 to 48 hours for a tick to pass Lyme disease to your pet, but clinical signs typically do not occur for weeks or months after infection. Additionally, only about five to 10% of infected dogs show clinical signs at all. In those dogs who do show signs, the following are most common:
- Shifting-leg lameness
- Enlarged lymph nodes
In some rare cases, Lyme disease can cause kidney damage, which may show up as a sudden onset of vomiting, weight loss, lethargy and increased water intake.
Lyme disease statistics
According to Petplan pet insurance claims data, Lyme disease continues to be the top claim for pets in the month of April. In fact, Lyme disease claims have been growing continually at Petplan, rising from $351 for the average cost of treatment in 2011 to $602 in 2017 — an increase of 72 percent in just six years.
While they don’t have the same ranking by severity as Lyme disease, the costs of other tick-borne illnesses, like anaplasmosis, are also on the rise, with average treatment amounts for 2017 coming in at $656 as opposed to $344 in 2011, representing a 91 percent increase.
The range of Lyme is spreading in the United States — and elsewhere, for that matter. Climate change is expanding the range of both the tick that causes Lyme and its reservoir hosts. Additionally, longer falls and earlier springs are extending the seasonality of ticks. Where once we could count on a long period of decreased tick activity in the winter, it's no longer a given.
And because of this continually increasing tick presence, veterinarians are making testing for Lyme disease a standard part of their protocol.
More veterinarians understand the importance of including Lyme as a rule-out for certain symptoms. Now that the tick habitats are expanding, vets are beginning to realize they should be testing for it. Thus, we’re seeing more positive tests.
Testing for Lyme in pets
There are many different types of tests for Lyme disease, but the current favorite is a test for specific antibodies that will show up in a blood test. Most veterinarians prefer to run a blood test called a C6 antibody. This test gives a quantitative value to assess the severity of infection, and makes it easier to decide whether or not treatment is recommended. While testing for Lyme disease is not complicated, deciding what to do with a positive result can lead to muddy waters.
If a dog tests positive for Lyme disease, he should be treated, right? Well, not exactly. Lyme disease in veterinary medicine is a complicated matter. From testing to treatment to prevention, there are many different opinions in the veterinary community regarding the best course of action.
Related reading: Lyme treatment, prevention strategies and their controversies.