It's officially tick season in Nova Scotia - and it looks like it's going to be a bad one.
I hate ticks. Pulling a tick off after a leisurely stroll or relaxing camping trip isn't only gross but it's such a drag when you have to deal with a whole bunch of them. And your dog never has just one, they always seem to have twenty or more. With this summer looking like it's going to be particularly tick-heavy and seeing a lot of misinformation circulating around the web, I thought I'd clear up some basic facts about ticks to help keep you, your fur-buddies, and your home as tick-free as possible.
What are ticks?
Ticks are a group of arachnid arthropods that parasitize the skin of birds, mice, deer, cats, dogs, humans, as well as host of other animal species. There are two kinds, the Ixodidae (hard ticks) and Argasidae (soft ticks), which both encompass a number of unique species. *There's actually a third kind called the Nuttalliellidae, but they're isolated to continental Africa, so I'm going to ignore them.
In Canada, the Argasidae are livestock pests, preferring cattle, chickens, though sometimes also wild animals like bats, and they are nocturnal, feeding rapidly and all at once during the night and leaving painful itchy spots, like bed bugs. These traits, combined with a low tolerance for Canada's cooler climate, means you're really unlikely to see them in Nova Scotia. In fact, there's only five confirmed species in all of Canada and they are currently limited to the South and West of the country. The Ixodidae, however, are much more diverse and more widely spread, they're out during the day, and some of them really love Fido. These are the ticks I'm gonna talk about:
Because ticks feed on blood, they can act as vectors for some pretty nasty blood-borne diseases that affect both humans and our furry pets. In Nova Scotia, they've been known to transmit Lyme Disease and other Borrelia-related diseases (a bacteria that, put very simply, affects the nervous and immune systems) and Granulocytic Anaplasmosis (a bacteria that targets certain white blood cells). Although there haven't been any confirmed human cases in our neck of the woods yet, they also carry Babesiosis (a protist that attacks red blood cells), Rocky Mountain Spotted Fever (a bacteria that causes a fever, rash, and can lead to encephalitis), and Powassan Disease (a virus that affects the nervous system and can also cause encephalitis and meningitis). Understanding tick biology and setting up proper tick control measures at home and outdoors is therefore essential for mitigating the risks of these serious diseases.
Knowing our local tick species
All species of tick go through four stages as part of their lifecycle: egg, larva, nymph, and adult. Most Ixodidae need a full year and three different "host" organisms to complete a full lifecycle. Eggs are usually laid on the ground and larvae emerge when conditions are warm to find their way to their first meal, usually unsuspecting small mammals and birds. They feed, mature into nymphs, and leave their original host to look for a larger one. Repeat, and you have an adult tick.
There are several tick species found in Nova Scotia that like to feed on humans and our furry companions: the most common of which is the "Dog" or "Wood" tick (Dermacentor variabilis), but also includes the "Blacklegged" or "Deer" tick (Ixodes scapularis), "Lone Star" tick (Amblyomma americanum), and the "Brown Dog" tick (Rhipicephalus sanguineus). There are, of course, many more species that infect other animals but that don't pose a risk to humans or our furry friends, either because of the environment they live in or because of a strict preference for these other hosts.
"What's in a name"
I hate the way we've named our ticks. The names "Dog" and "Brown Dog" are understandably confusing, as both are kind-of brown and both bite dogs. Using a host animal to describe a tick, as in the case of "Dog" or "Deer" ticks, is also useless for identification purposes, because ALL of these ticks like dogs, and deer, and people... ANNNND, scientific names (like Dermacentor variabilis) are either so technical or, often, just an excuse for some old white dude to name something after himself, that they are useless to the average hiker. So here are some nicknames I came up with to help me pass undergrad entomology and that you might find useful for IDing the ticks you find this summer:
Ixodes scapularis AKA Blacklegged/Deer Tick: "Little Blackleg Scutum"
This is the tick that carries Lyme disease, so you want to be able to ID it correctly. It also carries Babesiosis and Anaplasmosis, but I'll explain in a bit why I'm personally more concerned about Lyme. While it's not really black in colour (more like a dark brown) it is noticeably darker than the other species you're likely to see, so I like to keep "black" in my mind when I'm looking at ticks. It's also smaller than the others. Relative tick size can be hard to judge if you only have one in front of you, but remembering "little" might help you ID a blacklegged tick mixed in with some others. I also like to keep "scutum" in my mind. That's the little back plate found between the tick's head and the squishy part that fills up with blood. On the blacklegged tick, the scutum is very dark and, on females, it's small enough to see the contrast between it and the lighter, blood-filled abdomen. "Scutum" also sounds like "cute" to me, which helps me remember the small size of this not-so-cute, disease-carrying monster. Little Blackleg S-Cutem.
Dermacentor variabilis AKA Dog/Wood Tick: "Mottled White, Alright"
The dog or wood tick looks like a bigger version of the blacklegged tick, but it's colour is noticeably different. These guys have a stripey or mottled white and brown pattern on their scutum. Nymphs can be tough because of their size, but they are still lighter and more mottled than the blacklegged. They carry Rocky Mountain Spotted Fever, which is an awful Lyme-like disease that, so far, hasn't infected any humans despite its presence in Nova Scotia. Mottled White, Alright.
Amblyomma americanum AKA Lonestar Tick: "Red-blooded American" or "White-Spot 'Murica"
The lonestar tick is a little lighter in colour than the blacklegged or dog/wood tick, and I find it has a reddish tinge. The females also have a noticeable white spot on their scutum. We see a couple of these ticks every now and then, but there aren't any established populations in Canada, so you probably don't need to worry about them too much (yet). They do transmit, though very infrequently, an antibody that causes a strange allergy to certain meats. For a tick named after the steak-eating lonestar state, this anti-'Murican characteristic is tragically ironic.
Rhipicephalus sanguineus AKA Brown Dog Tick: "Long Brown Boi"
The brown dog tick is all brown, sometimes with darker stripey markings, but it's not the white mottling of the dog/wood tick and it never has spots. It's pretty plain looking. I also find its body is slightly more oblong than the others, having a skinnier and longer abdomen. Of course, a blood-engorged tick doesn't look skinny so that tip might only be useful before your tick has fed. The brown dog tick is supposedly found near kennels and other dog-dense dwellings, hence the name, but I have found them in abundance in the remote wilderness and in every corner of the province. Like the other "dog" tick, they carry Rocky Mountain Spotted Fever. They also carry a number of diseases that can infect dogs as well as humans, like the bacteria responsible for canine ehrlichiosis and babesiosis. Long Brown Bois are bad bois.
Why the fuss? I heard Lyme isn't even that serious
I'm dumbfounded when I hear Lyme- and tick-skepticism from other hikers. Being an ecologist turned dogwalker, I know I have some nerdier-than-usual books on my shelf, but there is a VAST amount of publically-available scientific support out there for both the severity of tick-transmitted diseases and the use of tested best practices for keeping humans and dogs protected from these horrible illnesses. I don't know if the pet-owning crowd have been affected by the larger anti-vax/fear of "big-pharma" movement sweeping the developed world, if our vets are so busy they're becoming rude and losing the trust of the general public, or if there's just that little knowledge of tick biology out there... But the lack of preventative tick care I see in Nova Scotia has me and other pet care providers concerned. Here are some of the most common and, I think, most serious myths that need addressing when it comes to ticks:
1) Tick-borne diseases aren't serious, aren't that common, or they don't affect dogs
I mean, I don't know how much you personally value your brain function or the ability to walk... but tick-borne diseases are really awful. And yes, dogs can catch these things too. Here's what you should know about each tick-borne disease in Nova Scotia:
Lyme Disease
Bacterial
(In humans) Symptoms vary greatly and are difficult to diagnose clinically, sometimes requiring blood tests. Symptoms may also go misdiagnosed for years because of the variation between cases and similarities with other diseases, including other tick-borne diseases. Most notable symptoms include skin rashes, paralysis, heart and neurological disorders, and severe permanent arthritis-like pain.
Like most tick-borne diseases, Lyme cases haven't been tracked for very long. Data is particularly sparse in Atlantic Canada.
"Confirmed" cases in Nova Scotia up 27X since 2007 (or as much as 54X if you include what Health Canada calls "probable" cases.) Over 150 Lyme cases were confirmed in Nova Scotia in 2016. Part of this increase may be attributable to improved diagnostic methods, but most of the rise has been attributed to increases in both tick numbers and the percentage of ticks infected with the bacteria.
"Confirmed" cases up 2.3X in New England and American Great Lakes states since 1997 (or as much as 3.4X if you include what the American Centres for Disease Control and Prevention calls "probable" cases.) Over 25,000 Lyme cases were confirmed in the States in 2017.
Case fatality rates unavailable (if patients die it's due to long-term systematic complications) but fatality is low. Lyme is a disease that attacks quality of life.
"Confirmed" canine cases are likely not adequately tracked in Nova Scotia, but according to the Companion Animal Parasite Council, confirmed cases that are voluntarily reported by veterinarians are up 4.3X in Nova Scotia, from 99 cases in 2012 to 426 in 2018.
Rocky Mountain Spotted Fever
Bacterial
(In humans) Symptoms similar to Lyme, plus increased risk of encephalitis.
Confirmed cases fewer than Lyme, but up 3.5X in the States since 1950, case fatality rate approx 0.5-10% depending on bacterial species (at the high end, that's comparable to Botulism, Diphtheria, Legionnaires, and SARS)
No known cases in Nova Scotia, though the bacteria is present in ticks here
Powassan Disease
Viral
(In humans) Symptoms similar to Lyme, plus increased risk of encephalitis and meningitis
Half of survivors have lasting permanent neurological problems, such as chronic pain, muscle wasting, and memory problems
Confirmed cases fewer than Lyme (basically a handful every year), but up 16.5X in the States since 2008, case fatality rate averages around 10% depending on the year (again, that's bordering the uncomfortably high area on the fatality scale...)
No known cases in Nova Scotia, though the bacteria is present in ticks here
Babesiosis
Protozoan
Mostly infects animals, with few species infecting humans.
Confirmed cases fewer than Lyme at under 2000 in 2014, but thought to be rising in the States
No known cases in Nova Scotia, though the bacteria is present in ticks here and dogs brought into New Brunswick from the States have been confirmed to carry the disease.
Granulocytic Anaplasmosis
Bacterial
Extreme flu-like symptoms that can usually be treated effectively if caught early, but delayed treatment can lead to organ or system failure and, rarely, death.
Confirmed cases fewer than Lyme, but up 16.4X in the States.
Two human cases in Nova Scotia, has also been detected in a horse, and dogs brought into Atlantic Canada from Toronto have been confirmed to carry the disease.
2) Lyme and other tick-borne diseases are easy to diagnose and can be cured
Lyme worries me more than other tick-borne diseases because its carrier, the blacklegged tick, is increasing both in number and range throughout Nova Scotia. Lyme is a particularly troublesome topic in the pet community because there's a lot we don't know about it, which I think makes it susceptible to misinformation. We don't know how many people have been infected with Lyme in Nova Scotia or how likely it is that you will get Lyme from an infected tick, though we do suspect the number of Lyme cases is much higher than previously suspected. That's because of something else we don't know: we don't know how to best diagnose Lyme. Lyme presents with such varied symptoms, both in form and severity, that it often goes undiagnosed or misdiagnosed as something else for years (and it doesn't always result in that circular rash). We also don't know how likely it is for dogs to catch Lyme from an infected tick, for similar reasons. We do know, however, that Lyme can result (in humans) in organ failure, life-long pain, sleep problems, concentration and speech problems, and serious fatigue (with organ failure, pain, and fatigue also seen in dogs). Lyme is slowly gaining attention and traction as a research and public education focus in Nova Scotia, so hopefully in time we'll have more information available to help people make informed decisions about their tick-control practices.
3) The treatments for ticks are worse than tick-borne diseases
There are a variety of tick treatments available to pet owners, including many preventative options. As with everything in life, they come with certain risks, especially when used incorrectly, and need to be thoughtfully considered before using. In the early 2000s, the American Environmental Protection Agency changed regulations around flea and tick medications after receiving a number of reports of adverse effects to a few topical liquid treatments applied between the shoulder blades. These medications had recently been released from what was previously a prescription-required process to being available over the counter, and most adverse reactions were found to be due to improper dosage, usage on the wrong animal (cat products on dogs and vice versa), and use on animals of improper age. Fear of flea and tick treatments has been growing since, with scared pet parents running instead to "natural" solutions like garlic rubs and "genuine baltic amber" collars (seriously, don't buy those, they are a scam). Now, this isn't to say that commercial products don't come without risk, but what we need to understand is that anything sold in Canada, including products made for pets, has been through a rigorous testing process to ensure, as much as possible, its safety for animal, human, and environmental health. It's not foolproof, but alternative treatments have not been tested. Let me clarify what I mean here, because I hear stories all the time from people with short-haired dogs who have "tested" their home-grown sunflower oil or other miracle-cure and apparently never see ticks.
A scientific test is not a collection of anecdotal results from Buddy-up-the-road and his one dog. If it was, grad school would have been WAY easier... Neither is it a facebook conversation between five, ten, even fifty people discussing their various experiences with different treatment strategies. Commercial product testing in Canada uses standardized procedures that incorporate measures of certainty into their assessment. It takes hundreds if not thousands of comparable observations to come to a statistical conclusion. That means we compare many different factors, including the substance itself, but also factors like application method, dosage, dog breed, hair length, hair texture, tick species, and skin temperature. Now, trusting the quality of the science coming out of some government lab in big-bad Ontario, understandably, makes some people uncomfortable, especially if you don't have the scientific background to critique the few publicly-accessible findings. But you do have a vet (and me, I'm always happy to answer dog- and science-related questions). If you're unsure about the science behind your tick treatment, the safety of flea and tick meds in general, or anything else, I am certain your vet will be happy to take the time to show you what they know. And if they aren't, or they're just kind of a jerk in general, get a new vet. Science communication is a part of the job in pet care and you deserve a professional who is just as good with people as they are animals.
If you're interested in buying local products, there is a spray product made in Nova Scotia that has been tested through a partnership with Acadia University and found to be effective at deterring ticks (at least in a petri dish): Atlantick, which uses lemongrass, witchhazel, and other oils also independently tested for their efficacy as mosquito repellants. Of course, any number of factors may make Atlantick and other "natural" products more or less effective for your dog. You should discuss your options with your vet.
* Can I just take a moment here to say something about the words "natural" and "chemical"? Because they get used a lot and as a scientist it always frustrates me. Chemicals make up everything in our Universe. Lemongrass and other "natural" substances have a chemical formula, because they are chemicals. A rock has a chemical formula (in fact there are many kinds of rocks all with different formulas and specialized scientists who study them). There's a very fuzzy line between something "natural" and something made by scientists, like me, in a lab. After all, what's the difference between isolating jojoba oil in the lab and boiling lemongrass at home? "Natural" is increasingly often just a word used to market a product, to sell you something. It's not a coincidence that organic "natural" products are more expensive than the others out there. Be careful with who you buy your pet care products from.
So what can I do? How do I even know if a tick bit me or my dog?
The hard bodied Ixodidae ticks have a painless, pretty-much unnoticeable bite, which is part of what makes them dangerous. Most tick bites go unnoticed, with the tick feeding, detaching, and falling off without any sign. It's usually not until a person develops symptoms of disease that a tick bite is confirmed. The best way to prevent a bite is to do regular and thorough checks. Ticks like warm sheltered places, so check the armpits, groin, neck, behind the ears, and between the toes (that goes for you and Fido). You'll know if a found tick has attached. Adults will be stuck to the skin and, depending on how long they've been there, fat with blood. Nymphs might be harder to see, especially the little Blacklegged nymphs, which don't get quite as fat and often look like a freckle or speck of dirt.
How do I safely get a tick off?
DO NOT squeeze, burn, or put any kind of substance on the tick. There are a lot of old-wives tales out there about different things you can do to "starve" or "suffocate" an attached tick, and they don't work (or, they haven't been scientifically verified to work). Ticks are virtually indestructible. Actually, keeping a few retrieved ticks in a sealed jar is a cool science experiment for kids, because they can live for SO LONG without oxygen! So "suffocating" them with petroleum jelly or some other substance isn't going to help you much. You also don't want to do anything to encourage the transfer of bacteria, viruses, or other parasites. The safest way to remove a tick without releasing its mouth and gut contents into your bloodstream is to twist it off from the head. Tweezers can do the job, as long as you make sure to grab close to the skin, but there are also tick-specific grabbers you can buy. These are my favourite: https://www.otom.com/en/ (you can also buy these at Canadian Tire and sometimes Hike Nova Scotia and other local groups will sell them as part of a fundraiser). A tick that's buried under the skin might need a doctor or veterinarian's help to remove, get yourself or Fido in for an appointment.
What if I suspect a bite?
You should document all the ticks you find on Fido, and on your own body, even if you don't suspect a bite. I know it sounds tedious, but nymphs can be really hard to ID and, as we know, it's hard to tell if you've been bitten. The Lyme-carrying Blacklegged ticks are the most important to watch out for, but other species do rarely transmit other diseases, so it's good to keep track. I keep dated photos of every tick I take off of myself and my dogs, with a tag for the location I think we picked them up at. I also keep some of the ticks if I think I might need a professional ID at some point; if I suspect a bite or if it's a hard-to-ID nymph. In most cases, removing an attached tick within 24hrs of attaching will prevent infection. This is your biggest advantage in the fight against tick-borne diseases, so do those checks!
You used to be able to submit ticks to the Museum of Natural History for ID until last year when their [wonderful] zoologist retired. Since then it's become pretty hard to get a tick ID in Nova Scotia. There is a lab at Mount A in New Brunswick that will ID ticks AND test them for borrelia for a fee, though they sometimes have research grants that can cover the cost. If you suspect a tick bite in yourself or your pet though, your first contact should be your doctor or vet.
What else can I do to prevent tick-borne illnesses?
Dogs can get a vaccination against Lyme, and it's pretty cheap. Fingers crossed we'll have one for humans in the near future.
Permethrin is a pesticide recently cleared for use in Canada known for its effectiveness against mosquitos. It is currently being trialed for ticks. Organizations that require their staff to be in the field for long periods of time, like the Canadian Forces and the organizations I used to work for, recommend permethrin clothing. It's not very common but I have found some at Marks.
Look for sprays like Atlantick or make your own using ingredients proven to be effective in deterring ticks, and consider using these in addition to your other tick treatments. Stay clear of miracle cure-alls like amber collars and sprays with substances not endorsed by your vet, especially if your pet is prone to skin issues or allergies.
Talk to your vet about the different tick prevention medicines available to you. They will take into account your dogs' age, medical history, and coat and recommend the best options.
Avoid long grass and other overgrown areas (as a field ecologist and dog walker this is just about impossible for me). Ticks wait for their prey by "questing", perching on long blades of grass and other high plant structures waiting to latch onto the next mammal that walks by. You can avoid them by avoiding their habitat.
Try out some strategic landscaping at home. Avoid grasses, plant tick repelling plants, and get some chickens! Chickens love ticks.
Become a deer hunter (actually). It's getting harder to control Nova Scotia's deer population as hunters age and aren't replaced by new ones. Deer (and formerly caribou), which carry ticks, used to be controlled by the resident wolf and human population back when we had caribou, wolves, and lots of hunters. An increasing deer population means an increasing tick population, so break out the country tunes and go shoot a deer.
Engage in some climate action. Ticks are moving north and it's likely we'll see more species moving into Nova Scotia as well as more cases of tick-borne disease in the near future. Support provincial and national policies that incorporate climate change adaptation. Ask your MLA and city councillors what they plan to do about ticks and Lyme disease.
Talk to your friends. Be wary of anecdotal "evidence", but take other people's experiences into consideration when comparing tick-prevention options. Consider where they hike, their dog's coat type, the dog's behaviour, and dates you encounter ticks. And ask questions (I like to tell people to find their friendly neighbourhood scientist. We are out there in the wild, we're just introverted and don't talk much). Go to the museum, get an insect and arachnid field guide, email an entomologist!
But most of all, try to enjoy your hikes without worrying too much. It's no fun living in fear all the time, so get dirty, play in the grass, and remember your tick checks.
Happy Adventuring!
Becky
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