Tick-borne Lyme disease and your pet
by Dr. Mike Mossop
Tick populations have been on the rise across Canada for several years now, and like it or not, these buggers are here to stay. With this rise comes an increased risk of tick-borne illness like Lyme disease that has received so much attention in the media for the serious health effects it can have in people. But what about our pets? Dogs and cats are affected differently from people and it’s important to understand these differences to decide how best to keep the whole family safe.
The blacklegged tick (sometimes also called the deer tick) Ixodes scapularis in eastern North America spreads Lyme disease. They tend to live in wooded or grassy areas, but can be found anywhere there is vegetation. While most people think of tick season as being in the spring and fall, in reality ticks show “questing” behaviour any time the temperature is even slightly above freezing; this means ticks are active even in January and February on unseasonably warm days.
The majority of people (about 80 per cent) will develop some combination of signs within a few weeks including a rash, flu-like symptoms and joint pain after being bitten by a Lyme-infected tick. In rare cases, there can also more serious long-term effects like neurologic abnormalities and cardiac arrhythmias. Conversely, most dogs bitten by a Lyme infected tick will never show any signs of illness. This is not to say the disease is a non-issue in our canine companions but their risk of infection following exposure is less likely (closer to 10 per cent) and the disease tends to be less serious and more easily treatable than it is in humans.
When dogs do get sick they show signs of lethargy, decreased appetite and sometimes swollen joints or lameness. These signs can take weeks or months to show up following the inciting tick bite and generally respond well to treatment with antibiotics. We occasionally see joint pain (sometimes mistaken for arthritis), or a specific type of kidney disease when long-term chronic infections go untreated. Lucky for our feline friends, they are even less susceptible than dogs. While they can still get other tick-borne illnesses, clinical Lyme disease in cats is extremely rare or even non-existent.
A dog or cat cannot pass Lyme disease directly to a person. But ticks can hitch a ride inside on our furry friends and subsequently infect the people they live with. Even if our pets are less susceptible than we are, keeping them tick free will help not only their health but that of your entire family.
Get in the habit of doing regular tick checks for both you and your pets, and know what to look for. A quick online search for “how to do a tick check” will yield lots of results. But keep in mind ticks are quite small and can be difficult to see in animals with heavy coats. For those pets, try using your hands to feel for something that resembles a “skin tag.” If you take a closer look and see legs moving, it’s a tick!
Know how to remove a tick if you find one. The technique is the same for both pets and people in that you want to grasp the tick as close to the skin as possible; use fine tweezers, or better yet, a product like the Tick Key or Tick Twister. Search for either of those tools on YouTube for some great how-to videos. Removing the tick as soon as possible will help reduce the risk of disease transmission. If removed within 24 hours, the risk of Lyme disease is significantly decreased.
The use of a tick-preventive medication is your best tool for pets that roam beyond the comfort of their home and city sidewalks. There are multiple prescription products available that are both safe and effective for both dogs and cats. There are pros and cons to each of these products and it’s recommended that you to talk to your veterinarian about which is best for your pet. Keep in mind that tick preventive medications are different from those that prevent heartworm disease (a different infection that is spread by mosquitos, not ticks), which can be a point of confusion. Also, tick prevention may be required for different parts of the year in different climates. Given the current state in the Ottawa area, I recommend tick prevention for at least 9–10 months of the year (roughly March to December). But in reality, the safer option is to treat year-round to prevent bites during the warms spells throughout the winter.
Vaccination against Lyme disease is possible in dogs, but not cats or people. If your dog travels with you to areas that are higher risk for Lyme disease (e.g. Kingston area, the Thousand Islands, New York State, Connecticut) or if you continue to find ticks on your pet despite using tick prevention, vaccination is probably a good option for your dog. This will lower the risk of getting Lyme disease but keep in mind that this risk is already low and the vaccine won’t deter ticks from biting or feeding on your pet.
Consider regularly screening your dog for Lyme disease. If your dog has a positive test but is not showing any signs of illness, the most likely scenario is that no treatment will be recommended. That being said, knowing your dog’s Lyme disease status will alert your veterinarian to the need for tracking a specific type of urine test to monitor for early signs of Lyme-induced kidney problems. It could also alter treatment if your dog starts showing signs of arthritis earlier than expected.
Dr. Mike Mossop is a veterinarian practicing as a locum at various clinics around the city. To find out more, or if you have an idea to submit for a future article, please visit www.doctormike.vet. Dr. Mike is not associated with or paid by any of the companies mentioned in this article.
