Lyme disease from a dog: Don't believe everything you read
InsideToronto.com published an article entitled "Unsuspecting resident contracts Lyme disease from pet dog". However, Lyme disease cannot be transmitted from dogs to people.
Lyme disease is a tickborne disease caused by the bacterium Borrellia burgdorferi. This bacterium is transmitted from wildlife reservoirs to people and pets by ticks that have fed on an infected animal, and then latch onto a person or pet.
The article reports that a woman and her son from Scarborough, Ontario, were diagnosed with Lyme disease after there dog was infected. The owner frequently walked her dog in the Rouge Valley and Morningside Park. After finding a tick on her dog, the owner took the dog to the vet, and it was diagnosed with Lyme disease. She and her son were later diagnosed. The fact that people and pets in the same house got the same disease does not mean that the dog was the source of infection. Lyme disease cannot be transmitted directly between people and animals; ticks must be involved. Additionally, ticks must be attached for approximately 24 hours to efficiently transfer the bacterium. So, if multiple people and a pet in the house got Lyme disease, they were all bitten by ticks, presumably while walking in the woods. (It's also possible that a tick could have been brought into the house by a dog, and then it jumped onto a person). Identification of Lyme disease in a dog does not mean that there is a risk to people from the infected dog, but it does indicate that people may have been exposed in the same manner as the dog, and they should pay attention.
The dog owner in this case is upset that her veterinarian did not warn her about Lyme disease. She wants the College of Veterinarians of Ontario (the provincial licensing body for veterinarians) to "require members to tell people when they may have been exposed to Lyme disease through a pet, as well as what the symptoms are." That's reasonable, to a point. Veterinarians should engage their clients with discussions about zoonotic diseases. If they identify a pet with a zoonotic infection, they should talk about the implications. Similarly, if they identify a pet with an infection to which the owner may have also been exposed (such as Lyme disease), they should mention the risk. However, requiring vets to talk about signs of disease in people starts to cross the line between veterinary and human medicine. Vets should introduce the issue and let physicians take over from there.
People in the Toronto area should not panic based on this report. Lyme disease is quite rare in Ontario, especially in the Toronto area, as the ticks that transmit Lyme disease are not commonly found there.Toronto Public Health reports that an average of nine cases of Lyme disease a year have been diagnosed in people between 1998 and 2007, and that most of these cases were acquired in the US.
Removing ticks
Your veterinarian, physician and/or public health departments should be able to tell you what diseases are of concern in your area. Regardless of where you live, if you and your pet might encounter ticks, you should know how to remove them. Prompt removal is the key. Most tickborne diseases aren't transmitted immediately. Rather, the tick must be attached for a period of time for infection to occur. Therefore, close inspection of your pet (and yourself) for ticks after spending time outside, is important.
The following tick removal tips come from the Centers for Disease Control and Prevention (CDC).
- Remove a tick as soon as you see it.
- Use fine-tipped tweezers to firmly grasp the tick very close to your skin. With a steady motion, pull the tick away from your skin. Then clean your skin with soap and warm water.
- Avoid crushing the tick’s body.
- Do not be alarmed if the tick’s mouthparts remain in the skin. Once the mouthparts are removed from the rest of the tick, it can no longer transmit Lyme disease bacteria.
- If you accidentally crush the tick, clean your skin with soap and warm water or alcohol.
If a large number ticks are present on your pet, you should contact your veterinarian for assistance. Typically, a product that kills ticks will be applied to your pet.
There are various anecdotal recommendations that should be avoided, including burning the tick off with a match and covering the tick with substances such as gasoline, petroleum jelly or nail polish.
Camping with canines - tick tick not!
The warm weather is just about here, and that means the start of camping season. Lots of people love to spend time in the great outdoors during the summer, whether it’s at a summer cottage on the lake, trailer camping in a park with electricity and running water, or roughing it in a tent in the peace and solitude of a more remote wooded location. And many people bring along their faithful companions – their dogs – who enjoy the experience just as much, if not more, than we do.But there are also dangers lurking in the forests – microscopic dangers carried by tiny insects and other bugs. Ticks in particular are problematic. Certain ticks can carry a number of diseases that can make dogs sick, including Lyme disease (caused by Borrelia burgdorferi) and Rocky Mountain Spotted Fever (RMSF)(caused by Rickettsia rickettsii ). Both Lyme disease and RMSF are more common in certain areas where the tick species that carry them are present. You can NOT catch these diseases from your dog, but both you and your dog can be infected by the ticks that carry them. People can also be exposed to these pathogens by accidentally crushing an infected tick while trying to remove it from their dog. Ticks must be removed very carefully to ensure that the entire tick is removed, including the head and mouth pieces, without crushing it. If you're not sure how, contact your veterinarian. Also, the sooner the tick is removed, the less likely it is to transmit certain diseases, so be sure to check your dog thoroughly for ticks when you come back from a walk in the bush.
The Minnesota Department of Health recently reported that the number of cases of (human) Lyme disease increased in that state in 2007. This could be because of spreading tick populations, more people participating in activities in tick-inhabited areas, or increasing awareness and diagnosis of the disease by physicians.
If you and your canine companion will be spending time in some of the wilder and woodier parts of the great outdoors, talk to your veterinarian about what you can do to protect your dog. There are vaccines available for Lyme disease and the bacterial infection leptospirosis (which is also transmissible to people). Flea and tick preventatives are also very important, and many of today’s products are very effective. People should always wear insect repellent when camping or hiking in the woods. Visit the Health Canada website for safety tips on using personal insect repellents. All dogs should be vaccinated for rabies, whether they go camping in the backwoods or they’re house-bound city-slickers.
