Intro my name is dr. Andrew Peregrine I'm a clinical pathologist at the Ontario Veterinary College and it's currently May of 2017 I came to the veterinary college here in Ontario 20 years ago in 1997 and at that time I asked my predecessor how much teaching was carried out on ticks that we find on dogs and cats and I was told you really don't need to bother about that because taiks are not an issue and they weren't back then but in the subsequent 20 years Lyme disease: is the risk of infection increasing in Ontario? things have changed dramatically in Ontario and elsewhere across Canada and what I want to do today is give an update of some of the things that have been changing with respect to risk of ticks and the diseases that they can be associated with so what I want to do firstly is talk about firstly the ticks that you can find particularly on people and our pets in Ontario and also say something a little bit about the bugs that they transmit to our pets and ourselves I then want to talk about the most important tick-borne disease in North America at the moment and that's Lyme disease what is it what does it look like in pets and ourselves I particularly want to address the question is the risk of lyme disease and exposure to ticks changing in Ontario and elsewhere in Canada it's particularly important to understand the entire lifecycle of the tick that's involved with Lyme disease and especially its association with wildlife to understand how things are likely to change in the future and lastly I want to finish by just making a few comments about what can be done both for ourselves and our pets to minimize the risk of tick exposure and development of Is it important to identify the tick? Lyme disease this picture here actually shows the ear of a dog that walked into a veterinary practice in Guelph and the first question whenever you find anything on a pet is to ask yourself what type of bug is it this is a tick and the question is why is it a tick where you can see four pairs of legs and essentially if you can see something on your pair to yourself with four pairs of legs it has to be a tick if you look carefully at this ticket she has hardly fed it's not engorged yet and that's very relevant when we start our asking the question well it's a tick am i or my pet going to get Lyme disease and I'll come back to that so the first question is what are the ticks that we actually will find on dogs or ourselves across North America well if you look in Ticks on dogs in North America Common name Lone Star Tick the veterinary textbooks this is the list of all the ticks and there's a large number however in Ontario there's essentially just two ticks that form at least 98 99 % of all the ticks we find on our pets and that's the American dog tick whose scientific name is derma Center very ablis and the deer tick Exedy scapularis why is it important to appreciate there are two because only one of those is associated with transmission of the bug that causes Lyme disease the other has no role so it's extremely important when you find a tick to know which one you are dealing with this picture hit these Ticks on Ontario dogs two pictures here show two unfed ticks that could be found on ourselves or our pets and they are the two ticks I've just mentioned and the question you always ask is well which one is it how do you differentiate them right behind the head is a large plate light structure referred to as a scutum and you need to ask yourself is it multicolored or is it all dark brown and if you look at the one on the left think you can appreciate the scutum the plate is multicolored that's the American dog tick derma Center very obvious and it plays no role in transmission of the bug that causes Lyme disease in fact in Ontario we essentially think it's a clean tick it doesn't transmit any pathogens any bugs to people are our pets that's not true further south in the US but it appears to be the case here in Ontario so what about the kick on the right well if you look at the scutum on that tick you can see it's all dark brown it's got long mouth parts and that's the black legs or deer tick the scientific name is exuded scapularis and that's the tick that's the vector of the bug that causes Lyme disease and the name of the bug that causes Lyme disease is Borrelia burgdorferi it's a type of bacteria here is a Borrelia burgorferi (Lyme disease) picture of that bacteria it's got a very characteristic appearance and the disease it causes in infected dogs or infected people is referred to as Lyme disease and it gets that name because it was first discovered in Lyme Connecticut on the northeastern seaboard of the US and so it was found there many many decades ago in fact it appears to be there I've been there a lot longer so it's not a new infection or disease in North America but it's certainly new essentially in Canada over the last two decades so the picture I just showed you were two pictures of unfed ticks the reality particularly on our pets is that we don't find ticks until they've been feeding for significant amount of time they have fur so they typically are well fed by the time we find them so I want to show you some pictures of ticks that are fully fed as I said that's how you would normally find them on your pet so here's a tick fully engorged on a dog actually it's in the in Guelph in southern Ontario and the question is which tick is it and just as the previous image I showed you don't let the large body that's filled with blood through you look at the plate or the scutum just behind the head and I think you can appreciate that if you look at it it's multicolored it's light and dark brown which means it's the American dog tick will my dog get Lyme disease no it's the wrong tick now there's a few important things to appreciate about every ticks life cycle and the reason we should understand this is because it helps us to realize where these ticks are likely to spread Tick life cycle to in the coming years the picture I just showed you of a fully engorged tick that's a tick who's been feeding on blood the ticks been doing that so that she can produce large numbers of eggs once she's fully fed she typically will drop off into the environment and lay the eggs and this picture on the right shows you a tick that's released hundreds if not thousands of eggs into the environment if the environmental conditions are suitable and that's typically outside and reasonable amounts of vegetation and humidity out of those eggs will hatch a larva we almost never see these they're tiny and they typically feed on wildlife species once the larva has fed on blood for instance on a rodent once it's fully engorged it drops off back into the environment where it molds it moats into a nymphal stage it's a little bit bigger those typically only feed on wildlife species and once they're fully engorged with blood they again drop off back into the environment where they molt into an immature adult and it's usually the immature adults and fed adults is what we find on our pets or ourselves so where do you find the larvae the first stage that hatches out of the egg for the American dog tick you find it essentially on wild rodents the nymphs you find typically on larger wildlife species such as rabbits and raccoons we do occasionally see them on dogs cats or people and the adults dermis enter very Ovilus the American dog tick typically found on Ricans kotas and those are the ones we typically find on ourselves or our pets what type of environment is that tick best able to live in well all the lifecycle stages have got to live happily off the host they feed on and the hosts need to be present and typically it's open grassy meadows young forests along the trails where we often go hiking is where you'll find them and typically we only find adults in the environment on ourselves or our pets in the spring and early summer so that's the American dog tick it's a great tick with respect to the fact it does not transmit the bug that causes Lyme disease here's another well-fed Deer Tick tick the first question to ask is does this look the same or different from the other tick I've just shown you you can see it's fully engorged but if you look at the plate behind the head it's all dark brown it is not multicolored and it's got long mouth parts this is the deer tick the black leg tick or the scientific name it scapularis this shows two pictures of Ixodes scapularis - deer (black-legged) tick the same tic unfed and the picture on the right shows you the tick that crawled up to at the top of a blade of grass you can see its front legs pointing out alright and what the tick is doing it's called questing it's waiting for you or your pets to walk past and then the tick literally will just transfer onto you or your pet takes do not hunt you they wait for you to come to them why is this the tick that's of the greatest concern to the public health agency of Canada well it's because it transmits multiple things that infect people but by far the most important thing it transmits is the bug that causes Lyme disease that's the bacteria Borrelia burgdorferi it does also transmit to other things that infect people one is called anaplasma phagocytose for them and that also like Borrelia burgdorferi infects our dogs and there is a third parasite that's extremely rare in Ontario called babesia microti that does also infect people now on this slide you'll notice for the first two bugs in brackets at the end I've indicated for DX plus and that refers to a diagnostic test that commonly carried out on dogs every year primarily to screen them for heartworm however the same test allows us to screen dogs for exposure to both Borrelia burgdorferi the cause of Lyme disease and anaplasma that also infects dogs and people and I'm going to come back to the data that we've obtained with that test a little bit later so how big are the different life cycle stages of the deer tick exiting scapularis Tick life-cycle stages - Ixodes scapularis shown here first is a picture of a larvae and I think you'd appreciate you essentially would never see it it primarily lives in the environment and feeds on wildlife but even if it occurred on us I think we typically miss it the nim are a little bit bigger again they're very small we rarely if ever find them on our pets however they are thought to be the primary stage associated with the transmission of the bug that causes Lyme disease to people so it is significant with respect to Lyme disease risk in people it's the adults shown here that are yet to feed these are the stages we typically find on ourselves and our pets typically fed for a short period if at all on people however they've often well fed by the time we find them in our pets now this is the tick that's brand-new to Ontario and back in 1997 when I came to the Ontario Veterinary College essentially at that point the only place in all of Canada where this tick occurred was Long Point on Lake Erie and since then this tick is established in multiple places across Canada the places where it is established are essentially areas where the life cycle shown here has been able to take place readily normally the adult ticks feed preferentially essentially on white-tailed deer they feed on the deer to get blood that they don't get infected with the bug that causes Lyme disease when feeding on deer but once the adults are fully fed they drop off into the environment and then they lay their eggs into the environment and so this is not going to happen indoors the tick needs to be outdoors to lay the eggs for them to remain viable and then they hatch and just like the other tick I mentioned when they hatch out of those eggs hatch larvae tiny little structures that are in the environment and they need to feed particularly on wild rodents to obtain a blood meal now the interesting fact about this tick if the mother is infected with the bug that causes Lyme disease none of the offspring that hatch out of those eggs are born infected so the obvious question is so how do they get infected and they get infected with the bug that causes Lyme disease when they feed on wild rodents such as white-footed mice how does that happen well the bacteria that causes Lyme disease essentially circulates in the blood of wild rodents typically doesn't make them sick but when the larval stage of the tick feeds on the wild rodents it takes in with the blood the bacteria and once the techs infected essentially it remains infected for life when the love is fully fed it drops off into the environment molt's just as the other tech into a nymphal stage and quite extraordinary nymphs feed on exactly the same species as the larvae feed on wild rodents so if the lava didn't get infected with Borrelia burgdorferi the cause of lyme disease the nymphs likely will so it maximizes the chance of the tick getting infected and once the tick gets infected as I said before it remains infected for life the library limps preferentially feed on wild rodents and once the nymph is fully fed it drops off again into the environment molt's into an immature adult and that's what we usually find on ourselves or our pets and for this lifecycle to establish you obviously need these wildlife species in the environment you need vegetation and reasonable levels of humidity for the ticks to survive in the environment so this slide just summarizes the hosts that we find larvae on and it's particularly white-footed mice and other wild rodents however also shown on that list of species is birds I'll come back to that in a second spires nibs we primarily find themes so you find them on wild rodents but we also find them on birds and for both larvae and nymphs that's extremely important because we believe one of the primary drivers for the establishment of this taking Ontario has been the migration of birds particularly from the northeastern seaboard of the US and the spring up into Canada because when ground-dwelling birds take off in the spring these ticks larvae and nymphs can be attached to the birds they'll stay attached for many days and when the bird takes off the ticks go with them and when the birds land when they arrive in Canada the ticks drop off into the environment the primarily feet find adults on white-tailed deer but you do find them occasionally on other wildlife species as well where is the perfect habitat for this particular species of tick it's particularly found on long long Bush grass on the edge of deciduous forests and that seems to be particularly good environment for finding this tick what time of the year do we find the tick well I mentioned for the other tick the American dog tick we find that in the spring and early summer and that is also true for this tick so in the spring if you see ticks in the environment it can Ixodes scapularis in Canada - seasonality be either the two ticks I've mentioned either the American dog tick or the deer tick however this tick is different and that is you also will find it in the environment in the fall in October November and early December and the reality is actually it's in the fall that is when the immature adults first appear in the environment so that's when we see them typically late September October November early December in southern Ontario and if they have not fed they then go dormant under the snow and so then with the adults we see in the environment in the spring so that's typically April May June time they are the ticks that survive the winter unfed and now they're waiting to feed so I think one of the obvious questions is so what influences the risk of exposure to these ticks for you and your pets well remember as I said before ticks do not hunt us they wait for us to go into Tick waiting to feed their environment so if we don't go outside if our pets don't go outside there is no risk of exposure to the tick that's associated with Lyme disease and this slide here shows you a number of images of a typical deciduous forest where these ticks can be found they typically crawl up grass-blades waiting for us to walk by so the bottom left-hand image shows you a trail to the forest and if you walked right along the center of that trail you wouldn't get exposed to the tick but as soon as you wander off into the large grow into the long grass that's where you're likely to get exposed to the tick now I mentioned back in 1997 this tick had never before been seen in Canada outside Long Point on Lake Erie however following the mid-1990s tick was increasingly being detected in multiple places across Canada and as a result of the concern from the public health agency of Canada about the bugs that transmits to people and our pets the public health agency of Canada started a system that was called passive surveillance and that is you your veterinarians or your physicians could submit texts to them they would identify them and test them for the presence of particularly of the bug that causes Lyme disease Borrelia burgdorferi they've been kind to show me some of their data and this is the map of Canada for 2008 where they received the deer ticks from ixodes scapularis and you can see most of the text they've received at the lab in Winnipeg in Manitoba come from a few places and that's right across southern Ontario right up to the Quebec border southern Quebec in multiple places across the Maritime Provinces and then in parts of southern Manitoba now whenever you find ticks for the first time in environment Health Canada rightly says well make sure you know is this what's called an adventitious tick that's a tick that's recently fallen off a bird or does it represent a population of actively breeding ticks and the reason that's a relevant question is if it's an adventitious tick one that's recently fallen off a bird it's very likely it doesn't represent an established population so there's not long term risk in that area however if it's part of an actively breeding population there's going to be a risk of exposure there year by year and the population is going to very likely expand its distribution and so over the fine 15 years or so following the first appearance of this tick another public health agency of Canada funded a lot of work in Ontario and elsewhere in Canada to try and determine where this pick was actively breeding and so this is the map for southern Ontario that indicated what it called the endemic sites where the ticks were actively breeding there's a lot of money and a lot of work goes into proving these sites exist you have to send people out to drag cloth across grass to look for the different lifecycle stages of the tick so you have to find all the different lifecycle stages you have to prove there feeding on wildlife and you have to prove the wildlife and the ticks are infected with the bug that causes Lyme disease it's a lot of work and that's what went into this particular map but the problem with that map is as soon as you publicize it the date that the data was found because it takes so long to prove that a site's endemic by the time you've proven it the maps out-of-date and so very recently I think a very sensible discussion has been taking place and that is how do you convey the risk of Lyme disease to physicians vets and the general public how do you convey it to maps using maps trying to make sure they're as up-to-date as possible using endemic area risk maps is essentially always out-of-date and so very recently certainly here in Ontario and public health Ontario has switched to a mapping system that's referred to as that that denotes Lyme disease risk areas and a lot less funds have to go in to denoting a Lyme risk area and this shows that June 2016 map for southern Ontario from public health Ontario each of those yellow spheres on the map indicate an area where the folks in public health Ontario have gone out into the environment and have dragged for ticks and they went out because members of the public physicians or that submitted ticks to them from that area they then went out dragged for ticks in two seasons click seasons and if they found them there in two six seasons that was concluded completely occluded to be sufficient evidence that it was now a risk area and they then put a twenty kilometre circle around where they found the tick to denote a reasonable risk area it's important to note 20 years ago essentially none of those areas existed and so that's the establishment in 20 years it was only a Long Point Lake Erie back in the mid 1990s what the area has changed most dramatically is Eastern Ontario however there are multiple other places on the northern shores of Lake Erie and Lake Ontario and many of those places represent places went bird where birds land when they first migrated up from the u.s. into Canada in the spring there the national parks the takes have dropped off there and they've established how quickly things can change is actually shown here this is a group of ticks that were pulled off a dog in Murphy's Point Provincial Park which is roughly halfway between Kingston and Ottawa five years before when this picture was taken you couldn't find the tick in that park this was taken in 2016 they're essentially 30 ticks found on a dog in that park after only a 30-minute walk they're engorge ticks the ticks were found a few days later on the dog so things can change particularly quickly and things are changing quickest in Ontario in Eastern Ontario the climate and particularly the environment appears to be perfect for these ticks so I think the obvious question is to what extent actually is the risk of Lyme disease increasing in Ontario where the change is greatest I think it's particularly useful to first look at what's been happening in the US because what happens in the US does Drive a lot of the changes that we are seeing in Canada and that's because of bird migration up here every spring this map here shows you the Centers for Disease Control's map for Lyme disease cases in people in the US in 2001 and the next map 2014 shows you a similar map for human cases of Lyme disease in the u.s. in 2014 so the first map is 2001 the second map of 2014 and as you can see in the 13 year period there's been a dramatic increase in the number of cases of human Lyme disease particularly in the northeastern seaboard of the US and it stores at least 70 80 % of all the Lyme disease case people occur in that area so it states like New Jersey New Hampshire Connecticut Cape Cod Rhode Island New York states now and so that's the big hot spot and remember that's where birds many birds take off in the spring and migrate up into Canada bringing ticks with them there is another hot spot just to the west of the Great Lakes in Minnesota and Wisconsin just look at that area that's 2001 2014 there's been significant dispersal now some of the increase in cases is almost certainly due to increased surveillance but that doesn't appear to explain much of this increase so what's been happening here in Ontario well this is a table that shows all the Outcomes of passive surveillance in 2007-2012 Ontario submissions ticks that the public health agency of Canada received from veterinarians and physicians in Ontario between 2007 and 2013 and it indicates the number of the deer ticks found on cats dogs and people over that period I think the important thing to appreciate is that at least two-thirds of the ticks they received came from people once the ticks were received the public health agency of Canada then examined the ticks to determine whether or not they were infected with the bug that causes Lyme disease and so the first column here that is reads Borrelia that means the number of ticks that were found to be infected with Borrelia burgdorferi the figure on the left is the number of ticks that were testing positive but what's more relevant is the proportion or the percentage of the ticks that tested positive and that's what's shown in brackets back in 2007 seven and a half percent of the ticks that were submitted to them from Ontario were infected with Borrelia burgdorferi and over the following years that increased dramatically up to eighteen point four percent in 2003 so in a seven year period essentially the proportion of the ticks infected with the bug that causes Lyme disease in Ontario almost traveled so now probably at least one in five ticks on average across the province are infected with the bug that causes Lyme disease what about anaplasma this is another bug I mentioned in the same tick that infects dogs and people and that stayed very low at less than 1% and if you look on the right on the number of locations in Ontario where ticks were found to be infected with the bug that causes Lyme disease it went up from 35 in 2007 to 163 locations in 2013 things have been changing dramatically in parts of the province now as far as the most thing that they can take home messages Proportion of Ixodes scapularis infected with Borrelia burgdorferi in Ontario Proportion of ticks infected concerned then with respect to you found a tick that is the deer tick exiting scapularis and you ask the question what's the chance it's infected with the bug that causes Lyme disease overall in Ontario at the moment as I just mentioned it's just above 18 percent and so on average one in five ticks is infected with the bug that causes Lyme disease if you travel across Canada so for instance if you go to Manitoba or the Maritime Provinces on average it's about the same figure just under one in five ticks appear to be infected if you go to Point Pelee in Ontario it's about a quarter of all the ticks 27 percent of the ticks appear to be infected and if you go to Long Point on Lake Erie where the ticks been the longest at least sixty percent of the ticks are infected in that location so where you live and where you travel to both in Canada and in the u.s. can change the risk of exposure to the tick and the bug that causes Lyme disease dramatically now Public Health Agency Ontario is doing routine surveillance for this tick and testing the tick for the bug that causes Lyme disease regularly and if you go to their website you can find the most most up-to-date information as is shown on this particular map that's currently available on their website for 2015 every dot shows you where they were submitted they received ticks from and the color of those Doc's dot indicates the proportion of the ticks that were infected and so for instance in Prince Edward County not only are there large numbers of ticks that were submitted but many were infected and so if you want the most up-to-date information on ticks that are being tested for the bug that causes Lyme disease go on to the public health Ontario website so there's clear evidence from ticks being submitted to public health Ontario and the public health agency of Canada but things are changing dramatically not only in Ontario but also in southern Quebec in the Maritimes in southern Manitoba but what about our pets well the reality is many of us are testing our dogs for exposure to the bug that causes Lyme disease every year you may not know that however many dogs especially Ontario are being screened every year for a test called the 4dx plus test and there are the similar ones and the primary reasons for using that is to detect to test the dog for heartworm which is an important thing to be doing but this test and some other similar ones at the same time with the same blood sample allow your veterinarian to determine whether or not the dog has got exposed to the bug that causes Lyme disease and developed antibody and so we actually have a lot Testing of dogs with 4Dx® Test of data for a lot of dogs in Ontario over many years and these types of data are not available for people but they are for dogs so for instance in Ontario back in 2007 we know that just over 68 and a half hours and dogs were examined with this test a year later in 2008 just under 57,000 dogs were examined and then very recently we've been able to get hold of the same data through colleagues Oklahoma State University and they got hold of the same data for Ontario for 2013-2014 we're just over seventy seven thousand dogs were screened so what was found well I think it's particularly interesting back in 2007 just in excess of 0.5% so that's less than 1% of the dogs in Ontario had antibody in their blood so very very few had been exposed and that's not surprising because this is a new infection and a new disease in Ontario a year later the figure had not changed in fact it was 0.447 percent for that half a percent of all the dogs had antibody in their blood but five years later in 2013 2014 the proportion of the dogs that had antibody to the bug that causes Lyme disease had gone from about 0.5 percent up to about 2.3 percent in all of Ontario and if you just look at Eastern Ontario it had gone up to 5.1 percent that's essentially it that's a significant increase in the number of dogs that have got exposed to the bug that causes Lyme disease now the next map shows you where all the Percent positive canine tests for antibody to Borrelia burgdorferi throughout Canada. United States data from previously published report by Little et al. for 2010-2012 dogs that are positive were being found and it's superimposed on the same map for the US and it's important to appreciate the darker the blue the greater the proportion of dogs that have got antibody that have been exposed to the Deer Tick and transmission of the bug into them that causes the disease lyme disease the very dark blue indicates in those areas more than 5% of dogs have been exposed where are those areas shouldn't surprise you right across southern Ontario but especially Eastern Ontario especially southern Quebec small pockets in the maritime provinces and then of pockets in southern Manitoba and you can see the speed counterpart areas that I've already described in the US and so if you or your pet travel into those areas all right the risk of exposure to the tick and the bug that causes Lyme disease changes significantly but do you remember if your dog's positive you're typically in the same environment as your dog and so if your dogs got exposed it's quite likely you've got exposed so what happens to your dog if it gets fed on by an infected tick well the answer is usually nothing and that is about 95 Typical clinical signs of Lyme disease in dogs -shifting leglameness, joint sweling, fever percent of dogs that get exposed and never become sick only about 5% do so most dogs seem to be resistant to the development of disease they get infected they develop antibody but they don't become sick if they do become sick it has many many months after the tick bite and it's usually two to five months after the pigs fed and then the dog develops our shifting it's an intermittent lameness often the swelling's of the joint so one leg is lame for a few days that disappears and then another dog leg a leg becomes lame so if you're ever suspicious your dog might have Lyme disease take it in to your veterinarian for an examination but the important thing is not to panic if your dog tests positive with the test i've mentioned because most dogs never become sick the situation in people is very different and so I think one of the obvious questions is what's the evidence that the risk of infection in people in Ontario is changing now fortunately Lyme disease in people is a reportable disease in Ontario and so the information has to be reported the important facts about the disease and people it's very different for dogs and that is in a significant number of people and it's usually somewhere between 60 and 80 percent of people that are fed on by infected ticks so 60 to 80 percent of those people go on to develop a very large red skin rash at the site where the tick said it's called erythema migrans and by definition it's more than five centimetres in diameter and it develops typically seven to 14 days after the tick feeds so it's very very different from a classic bug bite that occurs very quickly and is essentially never that size and so if you're in a tick area or you're concerned and you've got a skin lesion like that so a large red skin rash more than five centimetres in diameter go into your physician that's the first clinical sign of Lyme disease it occurs in at least three-quarters of people after that the bacteria spreads out of the skin elsewhere in the body and for the first month people will often develop flu-like signs and in those early stages of infection the the infection can be very readily treated in people as it can be in dogs however it's not if it's not treated at that point but tyria can spread elsewhere in the body and can cause significant complications if it's not treated so how does the medical profession confirm lyme disease and these these definitions can be found Lyme disease in people (Ontario) - April 2015 on the public health ontario website so there's three confirmed case definitions of lyme disease in people and if these this occurs these cases have to be reported by law so the first confirmed case of Lyme disease is a person that works walked into a physician who has this large red skin rash so it's more than five centimetres in diameter and that person's had a history of either living in or traveling into one of the Lyme disease risk areas and so physicians today are encouraged to have the Lyme disease risk map that I've shown you and as I mentioned that can be found the most current version can be found on Public Health Ontario's website so the first confirmed case definition for Lyme disease and people a large skin rash and you have a history of living in or traveling into an area which is known to be a risk area the second definition is you have clinical signs consistent with Lyme disease other than the skin rash you go to your physician and they do some tests on you that prove the bacteria is in you all right and that has to be reported the case of Lyme disease and the third confirmed case definition is someone that has clinical signs consistent with Lyme disease other than the skin rash they've done a diagnostic test that proves you have antibody they've not looked specifically for the bug but have shown antibody so you've been exposed and you have a history of living in or traveling into a risk area and if you fit into any of those three categories the physician needs to report that case because it's reportable now the nice thing about the reportable system is that in addition to those two definitions they also have two definitions that are referred to as probable cases because the obvious response when people hear those definitions is well what happens in areas where the tick is just established they're not on the map they're not known to be Lyme disease risk areas and so they've created two probable case definitions which are very similar to two of the first definitions of confirmed cases the first one is exactly the same as the first one I told you about and that is you go to your physician you have a large red skin rash more than five centimeters in diameter all right but you have no history of living in or traveling into what's known to be a risk area that needs to be reported as a probable case and that's great because it keeps us up to date with areas where things are changing which we know is what's happening on a regular basis the other probable case definition is people who have clinical signs consistent with Lyme disease other than the skin rash they found antibody to the bug in your blood but you've not lived or traveled to a risk area and that's referred to as a probable case as well so these probable cases should pick up people that have got infected with the bug that causes Lyme disease in areas we didn't know that take it established and we know things are changing dramatically for instance in Eastern Ontario the distribution of the tick is changing roughly 40 kilometers a year in some areas and so this map indicates the number of reported cases of human Lyme disease in Ontario from 2002 to 2014 in 2009 the definition changed into confirmed and probable cases that's why the green colors are different but the total number each year is comparable throughout this whole period and you can see there's been a dramatic increase in the number of human cases right from 2002 up to 2013 there was a drop in 2014 which was seen in the US and it's thought that being due was due to climate issues that year now one of the very interesting things is what happens when you look at when these cases of Lyme disease of being diagnosed and this map this a bar graph here shows you by month throughout the year when the human cases are being diagnosed in Ontario and you can see the vast majority of human cases of Lyme disease are diagnosed in June July or go and a little bit into September and the important thing to appreciate the clinical incubation period for people is typically about a month by the time they've gone into their physician so it's typically much quicker than in dogs so it's very likely these people are getting infected somewhere between May and August so there's very much a peak in diagnosis of Lyme disease during the summer months in Ontario so I think one of the obvious Why is the distribution of Ixodes scapularis changing? questions is so what is driving the change in distribution why are things changing so quickly well I've already mentioned bird migration in the spring is driving a lot of this the birds migrate up and they bring ticks in now that's been happening for many many decades so why if things suddenly change because bird migrations not it appears that there's been increase in tick numbers in the north eastern seaboard to a critical mass and finally enough ticks have been coming in on the backs of birds in the spring to establish and that's continuing there also have been significant changes in the deer population numbers across much of Canada white-tailed deer and that's changing certainly the risk of ticks because the more deer there are the more hosts there are four ticks to feed on one of the drivers for the changes in deer population has been reforest ation planting trees has brought me it more deer in but the other thing that's certainly been a driver is climate change and if you look at projected climate change across Canada from the Projected expansion of the range of Ixodes scapularis, the Lyme disease vector, in Canada year 2000 to 2008 II as has been done in this map here by researchers at the public health agency of Canada I think it's a very useful look into the future as to where this pick is likely to establish and on this map the most important areas to look at are those that are red the red indicates climate suitability that's essentially perfect for the tick it doesn't mean the environments perfect but the climate is perfect and you can see back in 2000 there were just a very few small areas the Niagara Peninsula parts of Eastern Ontario and a few pockets in in Quebec and that was it in the next 20 years so up to 2020 you can see there's a dramatic increase in climate suitability right across southern Ontario and parts of southern Quebec back if you then move on to 2015 and to 2080 there's a dramatic change in the distribution of Canada both Ontario Quebec and the Maritimes there's a dramatic increase predicted land area where the climate will become suitable for this tick it doesn't mean the tick will establish everywhere the climate and environment needs to be suitable for that now how realistic and accurate of these projections well if you go back to the year 2020 the change in climate suitability in Eastern Ontario almost exactly Maps what we're seeing and so because the environment suitable for that I think that's why we're seeing dramatic changes in tick distribution there haven't been the same changes in the southern part of the province whilst the climate suitable the environment isn't in many areas finally I think one of the practical issues is when you pull Will my dog get Lyme disease? off a tick the question vets and physicians hear all the time is am i or my pet going to get Lyme disease and there's some important facts to appreciate and to ask yourself when you pull a tick off the first question is is it the right tick and we've already gone over how to identify that is it the deer tick Exedy scapularis the next question is if it is the right tick has it said long enough to be able to transmit the Ixodes scapularis and Borrelia burgdorferi bug that causes Lyme disease all the data indicates is that this tick needs to have been attached and fed for an absolute minimum of 24 hours before it can transmit the bug that causes Lyme disease so if it's not engorged oh nice lightning Gorge even if it's the right tick there's no risk of Lyme disease if it has fed long enough it's fully engorged what's the chance that's infected overall the figure as I mentioned earlier on for Ontario it's just under 20% there's roughly a one in five chance however that proportion does change in certain hot pockets across Ontario remember in Long Point Lake Erie a few years ago 60% of the ticks were infected so that's asking the question is at the right tick what's the chance my dog or myself of God exposed what can we do when we go out into the environment to reduce or minimize the risk of Lyme disease in dogs or ourselves as far as our dogs concerned if there's ticks in the area where you go hiking with your dog you should go to your veterinarian to talk to them about the most suitable type of tick control product you can use and there are now a lot to choose from there are topical products so those are solutions you apply on the skin there are products given orally to dogs and there are also some collars and so you should go to your veterinarian and talk to them about what's most suitable always always if you've got tick concerns for your dog the first approach is to use a tick control product the other option for dogs and this is not available for people is that there are a number of vaccines for Lyme disease and dogs and the majority of people think they are of benefit for our dogs particularly if you live or travel into high-risk areas and so talk to your veterinarian to determine whether it's useful to vaccinate your dog in addition to using a tick product we have an extremely important thing and this is just as important in people all right is to remember the fact the tick needs to attach and feed for a minimum of 24 hours before it can transmit the bug that causes Lyme disease and so checking your dog and yourself and your family members every day for ticks is highly highly beneficial so what about people well the reality is we don't have all the great control products the ticks that we do for dogs so remember the times of the year when you're most likely to get exposed to ticks and so that's in the spring and the fall and if you're out in the woods at that time of the year you can minimize risk of exposure to ticks by just keeping off bushy long grass areas but the reality is we often wander off into the bush and so if you're going to be doing that it makes sense to wear long pants tuck them into your socks and ideally wear long sleeve shirts that means that if the tick attaches onto ourselves it's going to be on our clothes I then have to walk up our clothes until it can find an area of exposed skin and it's we're much more likely to find the tick crawling off our clothes than under our clothes because we didn't tuck long pants into our socks one other thing you can do to try and reduce the risk of the ticket attaching to our legs when walking through the bush is spray DEET on our clothes and on our skin and that acts as a repellent it greatly reduces the risk of ticks establishing or transferring to our skin however the reality is sometimes ticks do make it onto our skin they usually then crawl up our bodies to hot humid areas and the areas you're most likely to find ticks on yourselves or your groin your armpits and around the back of your hairline and so those are the areas to check the ticks on a daily basis and that's all the family members in addition to our pets they're usually no bigger than about a poppyseed size when they're first on us so they're not large and if they're attached ideally grab hold of the mouthparts right by the skin with tweezers and slowly pull out alternatively you don't want to do that go to your physician go to your public health people and ask them to do that for you so the last question actually the final exam Will my dog get Lyme disease ? questions just as we give the veterinary students here it is a picture of a tick pull off a dog and the question is will my dog or will I if this is off me get Lyme disease so is it the right tick is it the deer tick well the reality is yes it is well my dog get Lyme disease absolutely not if takers not fed so that's a great one to find and it's more common we find them like that on people than our pets look at this tick is this the right tick is it pedantic absolutely if you look at the plates or the scutum it's all dark brown and as long mouth card spots so it's the right tick has it said long enough oh yes it's very very well fed and so if it's infected it could have transmitted the bug that causes Lyme disease and so if you ever see a tick like this strongly encourage you to take it into your physician if it's off you or take it into your veterinarian if it's off your pet and they'll discuss the best management of that exposure with you so I hope that talk was helpful I hope it's indicated quite clearly Summary there's been a dramatic change in the distribution the takers that that associated with Lyme disease across much of southern Ontario and elsewhere in Ontario our risk of exposure to the tick and therefore Lyme disease depend on our lifestyle if we never go outside if our pets never go out live outside it's not a risk but if we do we can get exposed to the tick and if it feeds to the bug that can cause Lyme disease there are many things that we can do with our pets and for ourselves when we're out hiking every day to minimize the chance of ticks attaching and feeding and they're just simple practical tips and for instance if you go to Connecticut on the north eastern seaboard of the US where they've been living with this cake and lyme disease for a lot longer with us it's become part of the daily routine to do tick checks on all family members and our pets I think the important thing for us to appreciate about our dogs is they're typically very resistant to the bug that causes Lyme disease most pets that get exposed to the bug that causes Lyme disease don't become sick in people that's quite different so I hope that was helpful this last slide just acknowledges all the various people that have kindly contributed data as I've shown you and so that's people in the public health agency of Canada and colleagues at the Ontario Veterinary College and colleagues in the public health agency some public health Ontario Oklahoma State University and lastly colleagues at Ida X the voyages thanks very much for your time