Lyme disease is an emerging infectious disease at Allegheny Veterinary Service and within our practice area. As a result, we are constantly updating our diagnostic and treatment protocols. We now test all canine patients during their annual wellness exam and sick patients that present with lameness and fever when no other obvious cause is found. In addition, vaccination against Lyme disease is recommended as a core vaccine for all canine patients.
What Is Lyme Disease?
Lyme disease is the most common tick-borne disease in the United States. The disease was first identified in Lyme, Connecticut, in the 1980s. Human and canine cases remained primarily concentrated in the northeastern United States for many years. From 2005 to 2015, our practice diagnosed 2-3 cases per year. More recently Lyme disease has migrated into our area of West Virginia. In our practice, we have noted a sharp increase in cases since 2015. As of 2020, it is common in our practice to diagnose one Lyme-positive case each day. Overall, 25% of the dogs tested at our practice are positive for Lyme disease.
How Do Dogs Get Lyme Disease?
Lyme disease is caused by the spirochete bacterium Borrelia burgdorferi, and transmitted by an Ixodes tick bite after 2-3 days of tick attachment. These “deer ticks” live in outdoor greenery and feed on birds, mice, small mammals, deer, dogs, people, etc. Migrating birds bring infected ticks to new habitats. Lyme disease is not contagious between infected animals and people without a tick bite. An individual tick only feeds on one host each season. Nymphal ticks are mostly active in the spring; adult ticks are active in the fall.
How Will I Know if My Dog Has Lyme Disease?
Sometimes dogs show illness, such as eye problems or lameness, due to Lyme disease. Based on experimental studies, young puppies (6-12 weeks old) appear to be more sensitive, with a self-limiting illness consisting of 4 days of fever and decreased appetite, with limping occurring 2-5 months after the tick bite. Older puppies (13-26 weeks old) have a shorter, 2-day illness, and adult dogs show none of these clinical signs (“symptoms”) in an experimental setting.
How Do We Test for Lyme Disease?
Our hospital performs a screening test for Lyme disease (along with heartworm and other tick-borne diseases) on all dogs at the annual exam. In addition, dogs are often tested when presenting sick with fever from an unidentified source, lameness, or kidney disease. This test is a quick screening test performed with a small blood sample.
What if My Dog Is Positive on a Screening Test?
A positive result indicates that a patient has been exposed to Borrelia burgdorferi, the bacteria that causes Lyme disease. Not all animals that get exposed (test positive) will become sick. Up to 70% of positive cases may just be exposed and suffer no further problems. However, 5% of the cases that test positive can develop serious complications with potentially deadly consequences, such as “Lyme nephritis.”
What Further Tests Can Be Performed to Make Sure That My Dog Does Not Have Lyme Disease?
If your dog is positive for Lyme disease on our screening test during an annual exam: Our veterinarians will recommend checking a urine sample to determine whether there is kidney disease. In addition, our veterinarians may recommend a further blood test to estimate the level of infection.
What Is Lyme Nephritis?
“Lyme nephritis” is a rare but severe form of kidney damage that has been associated with Lyme disease in dogs. This appears more common in Labrador and golden retrievers. The earliest warning of Lyme nephritis is protein in the urine (proteinuria). ALL Lyme-positive dogs should be screened and monitored through urine samples over time for proteinuria, even if previously treated for Lyme disease, since treatment may not prevent the development of Lyme nephritis.
How Can I Prevent Lyme Disease In My Dog?
Vaccination: Due to the increasing risk and incidence of this disease in our area, we now recommend Lyme vaccination for ALL canine patients as part of the annual examination. This vaccination has very low risk and reactions are rare.