All About Lyme Disease

How does my dog acquire Lyme disease?

Lyme disease is caused by a bacteria called Borrelia burgdorferi. This bacteria resides in the deer tick (Ixodes scapularis), which can be found in Southern Ontario. If a dog is bitten by a deer tick larva, nymph or adult that is carrying this bacteria the dog can contract Lyme disease. The tick must remain attached for 24 hours to transmit the bacteria.


What symptoms does Lyme disease cause?

Many dogs have no symptoms at all. Some dogs experience the symptoms listed below:

  • Intermittent lameness
  • Fever
  • Anorexia
  • Enlarged lymph nodes
  • Painful and/or swollen joints
  • Kidney failure

How is Lyme disease diagnosed?

  • One month after a tick bite, a blood test can be performed to look for antibodies against Borrelia burgdorferi.

If the above test is positive, additional tests will be required.

To treat or not to treat?

Due to many dogs having positive antibody tests but having no symptoms, the topic of treatment is controversial.

Treatment is recommended if your dog has any of the following:

  • History of symptoms signs of illness
  • Evidence of kidney damage

The recommended treatment is with an antibiotic called doxycycline. This is given for one month or longer if kidney damage is confirmed.

Can I catch Lyme disease from my dog?

No, but pets may bring infected ticks into the household, which can attach to a human causing them to become infected. Humans often develop a rash, flu-like symptoms and later develop joint pains. In a small percentage of people, neurological and heart-related symptoms occur.

swollen knee

How can I prevent Lyme disease?

  • Reduce your families risk of picking up a tick by avoiding leaf litter, staying on trails, wearing protective clothing, wearing DEET and keeping dogs on-leash. Always check your dog for ticks after you have been for a walk and remove any that are found.
  • Put your pet on an oral or topical tick preventive during the year, when the temperature is above 4 degrees Celsius.
  • 3. +/- Lyme vaccination depending on your dog’s risk level

Written by Dr. Cara Page, DVM