April 27th
Lyme Disease and Ticks

Ticks and Lyme disease have been around for thousands of years. However, Lyme disease was only recognized in the United States about 50 years ago. The bacteria that causes Lyme disease, Borrelia burgdorferi, was officially classified in 1981. In the early 1970s, a group of people located around Lyme, Connecticut were suffering from serious and unidentifiable health issues. Researchers began describing the signs and symptoms of this new disease and called it Lyme, but they still didn’t know what caused it. In 1981, a scientist who was studying another tick-borne disease began to study Lyme disease. This scientist, Dr.Wilhelm Burgdorfer, found the link between the blacklegged tick and the disease. He discovered that a bacterium, carried by blacklegged ticks, was causing Lyme and the medical community named it Borrelia burgdorferi in honour of his discovery.

There are two types of black-legged ticks that can spread Lyme disease in Canada. Both are Ixodes species and are commonly, but incorrectly, referred to as deer ticks. The eastern blacklegged tick (Ixodes scapularis) is located in central and eastern Canada and the western blacklegged tick (Ixodes pacificus) is located in British Columbia. It is important to note that tick ranges are changing and growing yearly. Provincial and federal public health agencies track cases of Lyme disease in humans and share this data on their web pages.

A few years ago, veterinarians were primarily concerned with dogs that traveled to specific areas along the Great Lakes. At that time, ticks were uncommon in the rest of the province. Currently, ticks are more common and any dog is at risk. Lyme disease can develop when an animal or person is bitten by an infected tick. There is a long incubation period in dogs, typically a few months, after an infected tick bite. The most common signs include fever, lameness, stiffness and swollen joints. Affected dogs can also exhibit a decreased appetite and swollen lymph nodes. A small percentage of infections in dogs will result in kidney disease.

Blacklegged ticks transmit bacteria during feeding but not all blacklegged ticks carry the bacteria that causes Lyme disease. As such, not every dog who is bitten by an infected tick will develop signs of Lyme disease.

Tests for heartworm exposure in dogs generally include a test for B. burgdorferi antibodies. A positive result indicates exposure to the bacterium but does not mean that your dog is sick or in danger. Your veterinarian will provide you with advice and steps to take after a positive result, depending on whether your pet is healthy or showing some signs of exposure.

How do I prevent Lyme disease in my dog?

Unfortunately, ticks are a reality in southern Ontario. All pets that venture outside are at risk. In order to decrease the likelihood that your pet is bitten by a tick, a multi-pronged approach is necessary and involves environmental management, tick-checks, preventive medication and possibly vaccines.

Reduce tick exposure in your immediate environment and stay away from areas that are likely to carry large populations of ticks. Keep the grass in your yard short and remove piles of yard waste promptly. Avoid tick-infested areas near your home or cottage and do not let your dog off leash in areas where deer and ticks are present. Check your dog for ticks on a daily basis and ask your veterinarian about help with, or techniques for, removing embedded ticks.

Since ticks are active above 4°C, tick preventive medications are required almost year round in southern Ontario. Check with your veterinarian regarding the most suitable mediation for your pet and avoid buying tick medication that has not been prescribed by a veterinarian. Products purchased from pet and grocery stores are readily available but can be highly toxic to cats. Veterinarians stock topical and chewable medication that is both effective and safe for both cats and dogs.

For active dogs with a higher risk of tick exposure, Lyme vaccines are available. However, a Lyme vaccine is not meant to replace other measures, such as tick checks and preventive medications.  In areas where tick counts are known to be high or where a dog’s lifestyle places them at a higher risk, it is important to discuss vaccination with your veterinarian.

How do I remove a tick from my dog?

The best way to remove a tick is with tweezers. Gently grasp the tick as close to the skin as possible with the tweezers and pull it upward and off using gentle, slow and steady pressure. Avoid crushing the tick as this can increase the chance that the bacterium that causes Lyme disease (if present in the tick) will be squeezed into your dog. Take care not to twist or jerk the tick as this can cause the mouth-parts to break off and remain in the skin. If possible, wear gloves in order to protect your hands in case the tick’s body breaks open during removal.

Dispose of a live tick by putting it in alcohol, placing it in a sealed bag, wrapping it tightly in tape or flushing it down the toilet. Hands should be washed or cleaned with an alcohol hand sanitizer after glove removal or any direct contact with ticks.

Should the thought of touching the tick give you pause, call your veterinary clinic to assist with removal and proper disposal. Just remember that time is of the essence. If you are far out in the woods or notice the tick late at night, it is better to remove it yourself than leave it until the next day.

For more information about ticks, check out this CTV interview and article.