Rat-a-tat-tat (or Rin-Tin-Tin-Tin) …K9 Sentinels marching in

Rin Tin Tin.jpg

There are certain words that guarantee my interest, and a short list of these (in no particular order) would include: Dogs, Canada, Infectious, Food, and the names of my two human children (probably accessing the internet right now). As such, I was thrilled to see a review article featuring the first three, Dogs as sentinels for Human Infectious Disease and Application to Canadian Populations: https://www.mdpi.com/2306-7381/5/4/83

The publication takes on the valiant task of summarizing research utilizing man’s (or in my case, woman’s) best friend, Canis familiaris (aka the dog) as a sentinel for human infectious disease, i.e. dogs being sick with or that have had exposure to disease-causing pathogens acting as a flashing warning sign for risk to the 2 legged animal (i.e. you, me and…girls-it’s time to stop with the screen time!). As is no real surprise, the idea of using dogs as infectious disease sentinels isn’t very common and per the article is even more radical for us Canadians (only 3% of the included studies, or if you prefer 4/142).

Animals have long been used as human risk sentinels, and as someone who spent much of my childhood in Flin Flon, Manitoba (https://en.wikipedia.org/wiki/Flin_Flon) the author’s use of ‘canary in the coal mine’ was a great way to consider (and re-consider) myriad ways animals have worked to warn us of threats to human health- be these environmental or infectious disease related.

In many ways dogs are the ideal sentinel for human health risk and I’ve written about this before on the Pets and Ticks website, while paraphrasing (parroting) Public Health Ontario’s Systematic Review on Companion Animals and Tick-borne disease (https://www.petsandticks.com/companion-animal-and-tick-borne-dis), which identified considerably more studies (n =44). For the very few of us who do research with dogs acting as sentinels, the human-animal bond and wealth of shared environment, e.g. dogs sleeping in the same room,+/- on the bed, and sharing a life full of things both of us (i.e. dogs and people) need (i.e. snuggles and all items unconditional), makes dogs the ideal (and admittedly just plain fun) research warning bell.

Most of the research (76%) identified by the review was on the use of dogs to estimate seroprevalence (blood antibodies in most cases) to certain pathogens that can cause infections, such as those spread by Ixodes scapularis (black-legged) ticks, most commonly Borrelia burgdorferi (the agent of Lyme disease), but also potentially emerging anaplasmosis, babesiosis and Powassen encephalitis. In ‘Our true north, Canada’, the researchers pointed out that using dogs to look for: 1) viruses like California serogroup viruses, Chikungunya and West Nile, 2) bacteria and rickettsia such as, Rickettsia and Ehrlichia spp., and 3) parasites, like the worm Dirofilaria immitis (canine heartworm), should be strongly considered due to disease emergence caused by our homeland’s increasing hospitality to ticks, mosquitoes and other disease vectors.

Finally, the study concluded with what most of us who do this type of research already know…in order to achieve study ‘do-ability’ a number of critical factors are non-negotiable. I’ve summarized these (and added a few) to create a ‘Top 10 Needs for K9 Sentinel Surveillance Studies” list:

1.    Be very clear on what you are looking for, i.e. what disease, type of disease emergence, and/or range of disease spread

2.    Do the study in an identified risk (or emerging risk) region

3.    Ensure you have study participants (sentinel units) such as veterinary clinics and pet-owners who will participate, i.e. no sentinels = no study

4.    If you’re looking for something new (emerging), start with naïve (negative for the bug) dogs and follow them over time and space (see #2)

5.    Hope (really hard) that you can repeat your sampling. That means relying on your people (participants and sentinel units) and trusting that they will enable continued study participation (study engagement) and repeat that for as long as the study lasts. This is a big ask.

6.    Allow the researcher (s) time, so as to actually ‘do’ the study.

7.    Allow the researcher (s) funding, so as to actually ‘do’ the study.

8.    Be pet-ethical. Never forget that these dogs have a very important job in many cases- to be a beloved companion. So, don’t do any testing beyond what they are already receiving as routine care from their dedicated veterinary clinic, such as an annual blood draw. Think of them like your own pets i.e. they are not ‘study subjects’.

9.    Save your samples- so that if something changes (or a new test or disease emerges) you can go back and look for it (whatever ‘it’ may be)

10. Work with your community of dedicated pet-owners and sentinel clinics- they know the dog best- and can provide a wealth of information reaching far beyond a blood test. This can help you sort out health concerns, risk factors (for the dogs and their people) and put things like travel beyond or between regions into correct data interpretation contexts.

Working with our canine protectors is not a new concept, but it can be a novel for some researchers and particularly funding agencies. The review also does a nice job (IMHO) of emphasizing that enhanced communication and collaboration between doctors of all species (veterinary and human), is looking more and more likely to be the way to identify, increase knowledge and stay safe from intruding infectious disease, particularly in Canada.

It’s heartening to see that research such as the Canadian K9 Lifetime Study or Pet Tick Tracker are regarded as illuminating (at least by researchers from the land of bagpipes, whiskey & Gaelic), and I’ve no doubt that dogs will continue to shine a Lyme-light on ground-breaking studies, that similarly helps their humans.

Autumn is coming. And lepto may be more likely...

As a native of the Canadian prairies, for much of my life I was oblivious to the glory of fall, and the wonder of cooler nights, warm (but not hot) days AND brilliant red, orange and yellow foliage. However, now that I live in a part of Canada with a fall season > 1.5 weeks, my thoughts turn to the colour yellow for a more sinister reason than 5-star Atlantic Canada leaf-peeping. 

Yellow is the colour I associate with leptospirosis, and it’s a rather nasty bug (bacterium) that can infect and cause a range of illness in dogs. Vets typically diagnose leptospirosis as kidney (urine) and/or liver (jaundice) disease...which is why (for me), lepto = yellow. The bacterium is formally known as Leptospira interrogans, and in dogs we usually think about 4 serovars (strains of the bug) as key: L. canicola, icterohaemorrhagiae, pomona and grippotyphosa.

Typically, lepto is shed in the urine of animals like raccoons, rats and other rodents. These wildlife hosts also frequently populate urban (city and suburbs) environments, (e.g. Toronto where I think a raccoon is running for mayor), and then urinate into puddles or other water sources that dogs splash or wander through, thus becoming infected.

Lepto’s also a bug we tend to find in geographic ‘hot spots’ in N. America, and there’s been a few publications (from the U.S.A.) indicating these higher risk lepto locations (links below). A number of articles also show an increased risk during specific seasons, such as in northern climes, where we tend to see more lepto in late summer/fall…hence the title of this post and my hope to increase awareness and reduce dogs getting sick. 

Lepto links:

Spatial and spatio-temporal clustering of overall and serovars-specific Leptospira microscopic agglutination test (MAT) seropositivity among dogs in the United States from 2000 through 2007. Gautam, et al. https://www.sciencedirect.com/science/article/pii/S0167587710001649?via%3Dihub

Hotspots of canine leptospirosis in the United States of America. White, et al. 


Seasonality of canine leptospirosis in the United States and Canada and its association with rainfall. Ward, et al. 


I love puppies...

I love puppies...

I love puppies. However, somewhat ironically, in my day-to-day gig as a veterinarian it’s pretty rare that I get to see (much less snuggle) with them. There are a number of reasons for this, probably the largest one being that as an internal medicine specialist I don’t tend to see a lot of puppies or healthy dogs. In fact, most of the patients I (or my vet students) see tend to be sick, and more and more they seem to be ill with infections that are increasingly difficult to treat. 

Antimicrobial resistance (i.e. bacteria not being killed by antibiotics) is a problem in human and veterinary medicine. And while the focus (and burden) of this is frequently centred on human health care providers, the spotlight is on veterinarians as well. Where am I going with this you ask OR what does this have to do with puppies? (Besides the obvious awesomeness of puppies in general). Hang in there…

Antimicrobial stewardship is a topic that many people have never heard before, and even those of us who have can find the topic uncomfortable or just plain confusing. However, regardless of your definition of antimicrobial stewardship (or how many multi-syllable words you like to cram together), what it means is all of us taking the time to be more aware of things we can do to recognize that infection occurs (and worsens) when we forget to stop and think about the long-term effects of our choices (i.e. the stewardship aspect). And that’s true whether we are human health care providers, veterinarians, pet-owners, parents or just plain people. 

I think the other thing to recognize is that we all need to help each other be better about resistant infection-prevention (i.e. the antimicrobial or antibiotic choice portion) by accepting accountability for our actions. Resources that help with informing this include: Canresist (https://canresist.com), Do BUGS NEED DRUGS? (http://www.dobugsneeddrugs.org/wp-content/uploads/info-sheet-english.pdf), and AMMI Canada’s short and snappy ‘Symptom-free pee: Let it be’ (https://www.ammi.ca/?ID=127). These simple messages can help educate all of us to be more aware (and vocal) about things we may hear, observe or are told in our doctor’s office, veterinary clinic, at school, virtually any public place or at home. 

So, feel free to test out your awareness and commitment to stewardship (and my love of puppies) anytime this week (or next). An example might be to say “Michelle- Can you please wash your hands before you touch my dog?” And just watch me smile- and then head over to the sink so that I can enjoy the snuggle-fest AND respect your choice to help me keep your dog as safe as we both can.

June 21, 2018

Michelle Evason, DVM, BSc, DACVIM