tag:theconversation.com,2011:/au/topics/blacklegged-tick-61088/articlesBlacklegged tick – The Conversation2019-08-07T13:39:01Ztag:theconversation.com,2011:article/1212372019-08-07T13:39:01Z2019-08-07T13:39:01ZA tick detective wants to understand what drives tick abundance<figure><img src="https://images.theconversation.com/files/286806/original/file-20190803-117910-1nj9mk8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Middlebury Assistant Professor David Allen prepares to inspect a piece of canvas dragged through the forest to collect ticks.
</span> <span class="attribution"><a class="source" href="http://www.middlebury.edu/newsroom/archive/2018-news/node/579261">Todd Balfour/Middlebury College</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/287050/original/file-20190806-84240-i26yzq.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/287050/original/file-20190806-84240-i26yzq.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=171&fit=crop&dpr=1 600w, https://images.theconversation.com/files/287050/original/file-20190806-84240-i26yzq.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=171&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/287050/original/file-20190806-84240-i26yzq.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=171&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/287050/original/file-20190806-84240-i26yzq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=215&fit=crop&dpr=1 754w, https://images.theconversation.com/files/287050/original/file-20190806-84240-i26yzq.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=215&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/287050/original/file-20190806-84240-i26yzq.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=215&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em>The Abstract features interesting research and the people behind it.</em></p>
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<p><strong><a href="http://www.middlebury.edu/academics/bio/faculty/node/352418">David Allen</a> is an assistant professor in biology at Middlebury College who studies the ecology of ticks and tick-borne pathogens.</strong></p>
<p><em>What question are you trying to answer with your work?</em></p>
<p><strong>David Allen:</strong> I want to understand what drives blacklegged, or deer, ticks’ abundance and infection rate with the Lyme disease bacteria. We broadly understand what is necessary for the tick to live in an area, but have a harder time explaining why there are such tremendous differences in tick abundance in certain locations and during certain years.</p>
<p><em>Exactly how do you measure tick abundance?</em> </p>
<p><strong>Allen:</strong> We measure it by what is called “drag cloth sampling.” We drag a 1 meter by 1 meter white cloth along the forest floor. Ticks that are searching for a host, which we call questing, will attach to the cloth as it passes over them. At each of our plots we drag the cloth along the forest floor for 200 meters and check it every 10 meters. This is the standard way to measure tick abundance.</p>
<p><em>What spurred you to study ticks?</em></p>
<p><strong>Allen:</strong> I grew up in Vermont in the 1980s and 1990s. During that time I do not remember ever seeing a blacklegged tick or knowing anyone with Lyme disease. When I returned to the state in 2012 to teach at Middlebury College, I would get lots of ticks when hiking. My research was spurred by this rapid and dramatic change in the tick population here.</p>
<p><em>Why is your work important to the public?</em></p>
<p><strong>Allen:</strong> The incidence of Lyme disease and other tick-borne diseases has <a href="https://www.cdc.gov/mmwr/volumes/67/wr/mm6717e1.htm">increased dramatically in recent years</a>. If scientists in general could better predict where ticks are the most abundant, we could target tick control strategies or at least create prevention messaging to people in those areas, and then hopefully start to decrease the rate of Lyme and other tick-borne diseases. </p>
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<img alt="" src="https://images.theconversation.com/files/286812/original/file-20190803-117857-1p8l5v5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/286812/original/file-20190803-117857-1p8l5v5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=196&fit=crop&dpr=1 600w, https://images.theconversation.com/files/286812/original/file-20190803-117857-1p8l5v5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=196&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/286812/original/file-20190803-117857-1p8l5v5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=196&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/286812/original/file-20190803-117857-1p8l5v5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=246&fit=crop&dpr=1 754w, https://images.theconversation.com/files/286812/original/file-20190803-117857-1p8l5v5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=246&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/286812/original/file-20190803-117857-1p8l5v5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=246&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Blacklegged ticks can carry pathogens that cause Lyme disease in the nymphal stage when they can be hard to see on skin.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Deer_tick_Ixodes_scapularis.jpg">Centers for Disease Control and Prevention</a></span>
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<p><em>What’s important about ticks that most people don’t know?</em></p>
<p><strong>Allen:</strong> Ticks have three life stages: larva, nymph and adult. The second two life stages can transmit the Lyme disease bacteria. When most people think about ticks they picture the adult life stage. For the blacklegged tick this is about the size of a sesame seed. I think that most people don’t have a good picture of what a nymphal tick looks like and how small it is. <a href="https://www.ncbi.nlm.nih.gov/pubmed/27330093">Nymphs are responsible for most transmission of Lyme disease to people</a>, because they are so hard to see when they are feeding on you. </p>
<p><em>What has been the most surprising finding of your work?</em></p>
<p><strong>Allen:</strong> I am surprised by how much tick abundance can vary across locations or years. We <a href="https://bioone.org/journals/Northeastern-Naturalist/volume-26/issue-3/045.026.0307/The-Density-of-the-Lyme-Disease-Vector-Ixodes-scapularis-Blacklegged/10.1656/045.026.0307.short">have found</a> that in two sites, just three miles away from each other, one can have 20 times more ticks than the other. And then going from one year to the next, the same location can increase or decrease in abundance by four times. </p>
<p><em>What do you hope to study further?</em></p>
<p><strong>Allen:</strong> We just started to study the small mammal community. Blacklegged ticks take a single blood meal at each life stage. During the larval and nymphal life stages, these blood meals are typically from small mammals, like mice or chipmunks. It is from these animals that the ticks acquire the Lyme disease bacteria. My students and I have just started tracking the populations of these small mammals to better understand how they contribute to tick abundance and infection. </p>
<p><em>Any stories from the field?</em></p>
<p><strong>Allen:</strong> We bait the small mammal traps with a mixture of oats and peanut butter. It turns out that bears find this just as tasty as the mice do. One time after setting out 100 traps, we returned the next morning to find them all thrown about. Some were dented or even pierced through with bear claw markings.</p>
<p>[ <em><a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=thanksforreading">Thanks for reading! We can send you The Conversation’s stories every day in an informative email. Sign up today.</a></em> ]</p><img src="https://counter.theconversation.com/content/121237/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Allen is supported by an Institutional Development Award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20GM103449. The contents of this article are solely the responsibility of the author and do not necessarily represent the official views of NIGMS or NIH.</span></em></p>A tick expert explains his work trying to understand why the abundance of the parasites vary so much from location to location and year to year.David Allen, Assistant Professor in Biology, MiddleburyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1114162019-03-19T23:01:17Z2019-03-19T23:01:17ZTick, tock: The countdown to peak tick season is here<figure><img src="https://images.theconversation.com/files/264463/original/file-20190318-28496-nhhyk6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A female blacklegged deer tick crawls along a piece of straw.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>With spring comes glorious sunshine, warmer weather — and ticks.</p>
<p>Ticks and some insect pests can carry bacteria, viruses and parasites that may cause disease in humans. One in particular, the blacklegged deer tick <em>Ixodes scapularis</em>, is well-known for its ability to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5879012/">transmit the Lyme disease-causing bacterium, <em>Borrelia burgdorferi</em></a>. </p>
<p>For the most part, these ticks are inactive throughout the winter and begin to look for their next meal as seasonal temperatures warm up. </p>
<p>But as the global climate warms, it is more likely that some ticks will remain active through the warmer winters and can expand their habitats into new areas. Because of this, hikers and dog owners need to be watchful for ticks year-round to reduce the risks of getting sick.</p>
<h2>Cold adapted</h2>
<p>Ticks and other pests are prevalent in forests during the warmer months, from spring to fall. But where do they go during the winter and how do they survive the cold polar vortexes, inches of snow and frostbite-inducing windchill?</p>
<p>Animals use a variety of strategies to deal with the winter months. While humans layer on clothing and mostly avoid going outside during bone-chilling temperatures, other organisms employ sophisticated behavioural adaptations and biological technologies to face winter head-on. </p>
<p>For the common house mosquito <em>Culex pipiens</em>, hibernation is key to survival. The insect enters a dormant phase (called diapause) allowing it to stay mostly inactive through the winter. The female <em>Culex</em> mosquito, a possible carrier of the West Nile virus, builds up fat stores during the summer and fall that serve as energy reserves and insulation for the winter months. This source of energy is useful for mosquitoes after they seek out and settle down in the human-made structures, sewers and animal burrows that they use as shelter to help them <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2373331/">escape subzero temperatures</a>. </p>
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<img alt="" src="https://images.theconversation.com/files/264643/original/file-20190319-60949-yy29y3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/264643/original/file-20190319-60949-yy29y3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/264643/original/file-20190319-60949-yy29y3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/264643/original/file-20190319-60949-yy29y3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/264643/original/file-20190319-60949-yy29y3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/264643/original/file-20190319-60949-yy29y3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/264643/original/file-20190319-60949-yy29y3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Blacklegged ticks position themselves at the tips of grasses to seek out their next blood meal such as from passing dogs.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>Ticks, however, don’t enter diapause and are still able to bite and eat a blood meal under the right conditions. These blood-sucking parasites live close to their host organisms, and can sometimes spend their entire life cycle on one animal. They use a technique called questing to locate a host that will serve as their next blood meal. Ticks station themselves on vegetation such as tall grasses and assume a sit-and-wait position. This allows them to grab onto any warm-blooded creature passing by. </p>
<p>Humans have employed our own behavioural strategies to protect ourselves from ticks during the warm seasons of the year. We do this by wearing long-sleeved clothing and using protective sprays when going on hikes through wooded and grassy areas. </p>
<h2>Battle against the bite</h2>
<p>One of the main challenges we still face in our battle against the bite is the fact that ticks further adapt their behaviour depending on where they are located in North America. </p>
<p>For instance, blacklegged deer ticks will avoid questing in warmer southern regions such as in South Carolina, where the risk of dehydration pushes them onto the ground, mostly below the leaf litter. In contrast, northern tick populations are less threatened by drying out due to humid conditions, and are <a href="http://europepmc.org/articles/pmc5226345">more likely to quest</a>. </p>
<p>Interestingly, blacklegged deer ticks also have the ability to quest in <a href="https://academic.oup.com/jme/article/38/2/318/877734">temperatures as low as -0.6°C</a>. This means that deer ticks are not limited to seeking out hosts during the warm months alone, but can continue feeding well into the early and late winter. It is therefore important not to lower one’s guard when enjoying the outdoors in wintertime. </p>
<p>Ticks are most active when temperatures rise above 7°C. But don’t be fooled into thinking that ticks simply die when the harsh winter weather kicks in! In reality, deer ticks are likely to survive even the harshest polar vortex. </p>
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Read more:
<a href="https://theconversation.com/ticks-and-mosquitoes-bringing-more-diseases-what-can-we-do-96688">Ticks and mosquitoes bringing more diseases – what can we do?</a>
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<p>It is quite common for ticks to cluster in hibernation nests and seek refuge under the layer of soil and ground litter within forests, where the temperature is less likely to fall below zero. In addition, snow cover, which acts like an insulating blanket over ground litter, tends to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4844560">further insulate ticks</a> from the frigid winter air temperatures. </p>
<p>Much like other cold-tolerant organisms, ticks can also produce an <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2929727/">antifreeze protein</a> that helps them tolerate colder temperatures by preventing their blood and tissues from freezing.</p>
<h2>Looking forward</h2>
<p>Climate change and the warming of our planet have resulted in the expansion of blacklegged deer tick populations to more northern regions of North America, including the the states of Wisconsin and New York and the provinces of Ontario and Québec. </p>
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<img alt="" src="https://images.theconversation.com/files/264639/original/file-20190319-60959-1chnzik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/264639/original/file-20190319-60959-1chnzik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=435&fit=crop&dpr=1 600w, https://images.theconversation.com/files/264639/original/file-20190319-60959-1chnzik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=435&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/264639/original/file-20190319-60959-1chnzik.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=435&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/264639/original/file-20190319-60959-1chnzik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=547&fit=crop&dpr=1 754w, https://images.theconversation.com/files/264639/original/file-20190319-60959-1chnzik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=547&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/264639/original/file-20190319-60959-1chnzik.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=547&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">The characteristic bull’s-eye patterned rash after the bit from a blacklegged tick infected with <em>Borrelia burgdorferi</em>.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>Using climate change models and current tick distribution patterns, we can <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5730520/">now predict the impact of future climate change on the migration of ticks</a> and the potential health risks that these populations carry across Canada and the <a href="https://tickencounter.org/current_tick_activity">United States</a>. For example, the geographic distribution of the blacklegged tick is projected to expand and cover most of Atlantic Canada and Manitoba by the year 2070. </p>
<p>It is very likely that all seasons can be a tick season in some regions. This makes it especially important to engage in continued vigilance in spotting and avoiding these tiny pests, even when out for a walk during the winter months. If your dog disrupts a patch of nested deer ticks for example, it could bring home some unwanted guests. </p>
<p>So, what can we expect as the weather warms up and as long winter nights transition into sunnier spring days? You can be certain that a large number of ticks that were around last season likely survived this winter. They are simply waiting for the right cues — warmer temperatures and longer daylight hours — to emerge and begin their quest for their next blood meal.</p><img src="https://counter.theconversation.com/content/111416/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rosa da Silva is an Assistant Professor in the Department of Biology and School of Interdisciplinary Science at McMaster University.
Rosa da Silva has previously received funding from the Natural Sciences and Engineering Research Council of Canada.</span></em></p>Ticks are generally inactive in the winter and start to look for their next meal as temperatures warm up. But as winters warm, every season may become tick season.Rosa da Silva, Assistant Professor, McMaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1043632018-10-22T21:32:58Z2018-10-22T21:32:58ZHow to avoid Lyme disease while ticks are hungry in the fall<figure><img src="https://images.theconversation.com/files/241183/original/file-20181018-41150-11vjtoo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Expansion of the blacklegged and other tick populations across Canada over the last few years mean an increased risk of diseases like Lyme disease. It is wise to do a full body tick check on ourselves and our pets when we come in from the outdoors.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Fall has arrived. This is the season that transforms our forests with a beautiful display of colour and fills our kitchens with the smell of pumpkin pie and apple cider. It also brings something far less pleasant to our forests and hiking trails — blacklegged ticks. </p>
<p>In parts of central and eastern Canada, <a href="https://doi.org/10.1371/journal.pone.0193524">October and November are peak activity times for adult blacklegged ticks or “deer ticks”</a> (<em>Ixodes scapularis</em>). Spring is also a peak time for adult activity, while nymphal blacklegged ticks are active late spring and early summer. This means they are hungry for blood and will climb up onto low lying vegetation in the forest to wait for their meal. This might be a deer or a raccoon — or it could be you, me or our pets.</p>
<p>Aside from the inherent revulsion many people feel towards ticks, some species pose a risk to human and animal health. The blacklegged tick can transmit several pathogens — most notably <em>Borrelia burgdorferi</em>, <a href="https://www.canada.ca/en/public-health/services/diseases/lyme-disease.html">which can cause Lyme disease in humans, dogs and horses</a>. </p>
<p>Lyme disease in humans is a potentially debilitating disease that can cause long-term <a href="https://www.canada.ca/en/public-health/services/diseases/lyme-disease/symptoms-lyme-disease.html">symptoms like fatigue, joint pain, arthritis, facial paralysis and neurological disorders if left untreated</a>. In dogs, the <a href="https://doi.org/10.1111/jvim.15085">most characteristic sign is a shifting lameness</a>, usually accompanied with general malaise. In rare cases, it can lead to a form of kidney failure. </p>
<p>As a veterinarian and researcher, my work focuses on ticks and tick-borne diseases, specifically those that affect both humans and animals. Over the past few years, we have certainly seen dramatic changes in our tick populations in Canada. </p>
<p>While this doesn’t mean we should curtail our outdoor activities, it does mean we need to think much more carefully about tick prevention.</p>
<h2>Master hitchhikers</h2>
<p>Back in the early 1990s, the blacklegged tick population in Canada was restricted to Long Point, Ont. Over the past few decades, we’ve seen an <a href="https://doi.org/10.1371/journal.pone.0189393">ongoing expansion of its range</a> with thriving populations now found in <a href="https://www.canada.ca/en/public-health/services/diseases/lyme-disease/risk-lyme-disease.html">many areas of Ontario, Québec, Nova Scotia, New Brunswick and Manitoba</a>. </p>
<p>Ticks — which themselves have very limited movement — are masters at hitching a ride on other animals, particularly migratory songbirds. </p>
<p><a href="https://aem.asm.org/content/74/6/1780">Each spring millions of ticks, blacklegged and other species, are introduced into Canada on migratory birds</a>. Not all of these ticks will survive and reproduce but this does provide a seed for population expansion. </p>
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<img alt="" src="https://images.theconversation.com/files/241287/original/file-20181018-67161-1w7nll9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/241287/original/file-20181018-67161-1w7nll9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=440&fit=crop&dpr=1 600w, https://images.theconversation.com/files/241287/original/file-20181018-67161-1w7nll9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=440&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/241287/original/file-20181018-67161-1w7nll9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=440&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/241287/original/file-20181018-67161-1w7nll9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=554&fit=crop&dpr=1 754w, https://images.theconversation.com/files/241287/original/file-20181018-67161-1w7nll9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=554&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/241287/original/file-20181018-67161-1w7nll9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=554&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">The lone star tick – one of several migrating tick species – is sporadically introduced into areas of Canada.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>Spring bird migration is not a new phenomenon. But what is changing is our climate along with other ecological factors — such as host populations and habitat — that facilitate blacklegged tick survival and population growth. </p>
<p>Sufficient temperature is a basic requirement for many tick species. Temperatures need to be warm enough for long enough so the ticks can feed and undergo development. <a href="https://doi.org/10.1186/1476-072X-7-24">With climate change, more northern areas are becoming more suitable for blacklegged ticks</a>. </p>
<p>Climate change also impacts <a href="https://doi.org/10.1093/jmedent/43.2.403">forested habitats</a> and the <a href="https://doi.org/10.1371/journal.pone.0080724">distribution of wildlife species</a>, all of which may <a href="https://doi.org/10.1111/eva.12165">further facilitate blacklegged tick range expansion</a>. </p>
<h2>New ticks on the block</h2>
<p>And it’s not just blacklegged ticks — we’ve seen notable changes in other tick species.</p>
<p>The lone star tick (<em>Amblyomma americanum</em>) has spread dramatically from the southern United States northward. Although no populations are known to exist in Canada, they are <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0105358">frequently introduced on birds</a>. <a href="https://doi.org/10.1093/jme/tjv150">Recent research</a> indicates that many areas are climatically suitable, with the appropriate habitat and hosts to support this tick species.</p>
<p>Last November, an exotic tick species from Asia — the longhorned tick (<em>Haemaphysalis longicornis</em>) — turned up on a sheep farm in New Jersey. It’s now been <a href="https://www.aphis.usda.gov/publications/animal_health/fs-longhorned-tick.pdf">found in over half a dozen states</a>. </p>
<p>What makes this tick species unique is that an adult female does not need to mate to produce viable eggs. This means a population can quickly become established in a new area following the introduction of this tick.</p>
<p>We do not know if or when these species could arrive in Canada. But, the blacklegged tick has illustrated that we must remain vigilant to monitor the distribution and spread of all ticks. </p>
<h2>How to do a full body check</h2>
<p>The public plays a large role in monitoring for ticks. Public health officials in many provinces accept tick submissions found on humans — <a href="https://www.canada.ca/en/public-health/services/diseases/lyme-disease/removing-submitting-ticks-testing.html">a process called passive surveillance</a>. </p>
<p>Other programs exist through research institutions. Researchers at the Ontario and Atlantic Veterinary Colleges run the <a href="http://www.petsandticks.com">Pet Tick Tracker</a>, which accepts submissions of ticks from pets.
Dogs are particularly good at picking up ticks from the environment and <a href="https://www.publichealthontario.ca/en/eRepository/Companion_Animals_Systematic_Review.pdf">may provide an early warning signal that disease risk is changing</a>. </p>
<p><a href="https://www.etick.ca/en/">eTick</a> is another online platform developed at Bishop’s University where the public can submit a photo of a tick for identification. It is currently only available in Québec but there are plans to expand to other provinces. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ySoDjoZt7yI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">University of Manitoba tick expert Dr. Kateryn Rochon explains how to check for ticks.</span></figcaption>
</figure>
<p>Unfortunately, once tick populations establish, it seems like they are here to stay. But this does not mean you should stop going outside and enjoying mother nature. It just means that we need to <a href="https://www.canada.ca/en/public-health/services/diseases/lyme-disease/prevention-lyme-disease.html">think more about tick prevention</a>. </p>
<p>There are many things we do to keep ourselves healthy. We wash our hands before we eat and put sunscreen on before going outside. And now when we come back inside, we must do a <a href="https://www.cdc.gov/features/stopticks/index.html">full body tick check on ourselves and our pets</a>.</p><img src="https://counter.theconversation.com/content/104363/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Katie Clow received funding from the Natural Sciences and Engineering Research Council of Canada (NSERC). She has delivered educational talks to veterinary professionals that were sponsored by Zoetis, Boehringer Ingleheim and Merck. She is affiliated with Veterinarians Without Borders Canada.</span></em></p>Fall is peak activity time for adult blacklegged ticks, increasing the risk of tick bites on both people and pets.Katie M. Clow, Postdoctoral Fellow, University of GuelphLicensed as Creative Commons – attribution, no derivatives.