Virginia Simpson and Chance


























Lyme Disease in Dogs

by Elizabeth Gigis, DVM, West Chester Veterinary Center




Recent reports by passive surveillance agencies in charge of monitoring tick populations indicate the population in Ohio of a common tick that carries Lyme disease is increasing dramatically.  Previously, Ohio was not considered a Lyme disease endemic state.  It was not understood exactly as to why many border states would report large numbers of Lyme disease, while Ohio numbers would remain relatively low.  Ohio does have a good climate for harboring Ixodes scapularis (the black legged tick), one of the carriers of Lyme disease.  Surveillance agencies with the Ohio Department of health are noting an increase in black legged tick populations over sixty times higher than in 2010.  As the black legged tick populations increase in Ohio, there is great potential to see an increase in the number of Lyme disease cases.

In the spring time, black legged ticks transmit infection to feeding larvae and nymphs (immature ticks).   These larvae primarily infect rodents and small mammals, whereas adult ticks will infect deer and other large mammals.   Nymphs and adult ticks will normally infect humans and pet dogs.   After the tick attaches, the spirochete bacteria that cause Lyme disease enter the dog’s body spreading to many different areas.  Lyme disease bacteria can spread to the joints, connective tissue, heart, and kidneys.  A few weeks after infection, the bacteria is present only in very small quantities in the tissue, but it is the immune system’s response to the infection that causes the majority of symptoms.  Usually, illness begins 2-3 months after the tick has attached.  Symptoms may include loss of appetite, fever, swollen lymph nodes, increased drinking or urination.  Lameness may also be present in one or more limbs.   Lyme disease is treated with one or more courses of common antibiotics, such as doxycycline.   There is a simple in house test made by Idexx that can detect if your pet has been exposed to Lyme disease.  If pets have clinic signs and a positive test for Lyme disease, the treatment is inexpensive and very safe.   Lyme disease may cause long term sequela including chronic arthritis and chronic kidney disease.   The organism may be difficult to get rid of completely and this can cause disease relapse.

In people, Lyme disease causes a characteristic “target lesion” rash on the skin.  While very common in humans, the target lesion is present in less than 30% of affected dogs.  Absence of a target lesion where the tick was attached does not mean that a pet is not infected with Lyme disease.   There are several important measures of prevention for your pet.  First, there is a vaccine available in dogs which protects  against Lyme disease.  Dogs in endemic areas or dogs exposed to tick environments on a regular basis should have this vaccine annually.   Second, have your pet on a monthly tick prevention product.   The tick must be attached for at least forty-eight hours in order to spread the spirochete bacteria that cause Lyme disease.  Frontline, Revolution, Certifect, and Advantix are all tick prevention products that will cause the tick to detach in less than 48 hours, thus preventing the spread of the bacteria.   This simple preventative measure will protect you and your pet from Lyme disease.  Enjoy your spring!

Elizabeth Gigis, DVM
West Chester Veterinary Center
7330 Liberty Way, West Chester, OH 45069
www.wcvetcenter.com
513-755-2273