Guest Blog by Dr. Michelle Evason DVM DipACVIM, and current PhD student researching Lyme disease in dogs
Recently, an interesting article on pet ownership and human tick risk was published (Jones et al, Zoonoses and Public Health 2017). The study looked at risk factors for “tick encounters” in people living in Lyme disease endemic states in the US.
Somewhat unsurprisingly (for anyone who likes to pet & play with their pets or allows them outside), the study found that people who owned pets had 2x the risk of finding ticks crawling on them (and 1.5x the risk of tick attachment) compared to households that didn’t have pets. While I’m really hoping that anyone reading this doesn’t decide that getting rid of their dog, cat, horse or other is my recommendation to solve this concern… I am REALLY hoping that people DO consider protecting their pets from tick attachment through the use of veterinary approved prevention methods (if they aren’t already), regular tick checks of their animals (especially prior to letting them sleep on the bed), and also strongly hoping that people consider protecting themselves (and their children) with tick prevention methods when they are outside (with or without their pets) in areas that are higher risk (e.g. forest, long grass) or if they live in declared Lyme endemic regions of Canada.
Ticks are a hot topic in parts of Canada, as they’re spreading pretty steadily across some parts of the country. There are lots of ways to prevent Lyme disease (or a number of other tick-borne diseases), and still enjoy the beauty and bounty of the Canadian summer and fall… and they all begin with awareness of why and how disease occurs. Right now, in Canada one of the increasing causes of clinical infectious disease illness in people and their dogs (and horses) are TICKS! This link from the CDC is a great guide to ways to provide protection from ticks in humans, and your veterinarian is an excellent guide to information on prevention for any 4 legged friends you may choose to co-habitate with.
As plenty of you know, there is a current lack of consensus regarding many of the clinical questions (diagnosis, treatment, prognosis) the veterinary community has about dogs (and horses) infected with Borrelia burgdorferi, the agent of Lyme disease.
These clinical questions about Lyme disease exist across species (i.e. canine, equine and human) and while I am frequently confused about what the term “One Health” actually means, if I get to choose a definition this would be it: Various animals (yes – humans are animals) infected with the same bug and getting a similar disease from it. So, it’d be great if we could all just team up and pool our knowledge on the topic. To be fair, Lyme is an extremely difficult disease to research outside of the lab; clinical Lyme disease is very hard to reproduce experimentally and we think only a very small percentage of dogs exposed to Borrelia burgdorferi via Ixodes tick bites develop disease. Furthermore, it’s not as if zero research on this particular pathogen is occurring, and if it was an easy disease to study we’d already have the answers to these questions… and it’s pretty clear by now that we just don’t.
Wouldn’t it be great if someone (or a group of someone’s) came along and decided to develop a study that followed young dogs along and watched, looked and listened to their devoted owners and veterinarians about what happened if/when they were bitten by a tick carrying the agent of Lyme disease, so we could move past (or try to) this lack of consensus and information and find some answers for all of us? Unfortunately, studies like this are hard to do, mainly because it’s tough to get people to take the time to enroll, answer questions and then do so repeatedly. It’s also tough to get funding for research that takes this kind of time, and as such longitudinal/lifetime studies are challenging to perform and to some degree are a total academic gamble. On the other hand, research studies like this have been attempted and done quite successfully in humans, such as the groundbreaking Framingham heart study and more recent Guelph Family Health Study.
Both of these have helped (and likely will continue to help) answer a great number of clinical questions that have paved the way to clearer understanding of disease, and perhaps even more importantly prevention. That’s why we’ve recently launched the Canadian K9 Lifetime Lyme Study and are part of a similar initiative in the USA, to try to answer some of these questions. More to come on those…