Ticks, ticks, ticks!

In this episode of the Wildtalk Podcast, we replay one of our most popular interviews about one of everyone's least favorite woodland insects — the tick.  

Episode Hosts: Rachel Leightner
Producer/editor: Eric Hilliard

• Michigan.gov/Lyme
• Radio Lab Podcast - Meat Allergy Episode
• The Tick App

Questions or comments about the show? Contact the DNR Wildlife Division at 517-284-9453 (WILD) or email dnr-wildlife@michigan.gov.

Transcript

Announcer:

The Michigan DNR Hunt Fish app is your digital connection to all things hunting and fishing in Michigan. Buy store and display your hunting and fishing licenses. Check your points and chances for elk and bear. Apply for the draw and view drawing results. Access all the hunting and fishing regulations. View your Hunter safety certificate and report your harvest all from within the Michigan DNR Hunt Fish app. Just click the app banner at the top of the page for download instructions at michigan.gov slash hunting.

You know what that sound means. It's time for the Michigan DNR'S Wild Talk Podcast. Welcome to the Wild Talk podcast, where representatives from the DNR'S Wildlife Division chew the fat and shoot the scat about all things habitat, feathers and fur. Everybody with insights interviews and your questions answered on the air, you'll get a better picture of what's happening in the world of wildlife here in the great state of Michigan.

Rachel:

Hello everyone, and welcome to the June episode of the Wild Talk podcast. This is your host, Rachel Lightner. I hope your summer is off to a great start so far and that you've been getting plenty of time in the outdoors. On today's episode will be returning our attention to a creature that may be small in size but can carry a big impact. And that is the tick. Pulled from the vault is our Ticks, Ticks, Ticks episode with Dr. Jean Soule, Dr. Megan Porter and Dr. Dan O'Brien. We love recording this episode and learning more about the eerie world of one of nature's most peculiar creatures. And we hope that you will love it, too. Later, stick around for your chance to win a wild talk podcast camp mug. But first, let's hear a word about our forests.

Announcer:

Trees provide for the wellbeing of our state. That's why we work so hard to keep our forest healthy and abundant so wildlife has a home and so do people so that there's clean air and water for everyone. And so Michigan's economy can be as strong as the trees that support it because every branch of forestry ensures that future generations will always have a tree for life and forests for a lifetime. To learn how sustainable forestry benefits your life, visit michigan.gov/forestsforalifetime.

Holly:

Today, here in studio, we have Dr. Dan O'Brien of the DNR Wildlife Disease Lab and Dr. Jean Tsao of... She is an Associate Professor of the Fisheries and Wildlife Department over at Michigan State University. And we have Dr. Megan Porter, a graduate student, also at Michigan State University. Welcome to all three of you. Thank you for being here today.

Dan:

Thanks for having us.

Jean:

Thank you.

Holly:

Today we're talking about ticks, and we are finding more and more lately with our phone calls and emails that we get into our department, people are looking for tick related information and have concerns about ticks. And growing up, I don't really remember ticks being much of an issue in Michigan. It seems like things are changing. Has something changed or was I just unaware of the tick situation when I was younger?

Jean:

Holly, I think the situation is changing, and this is largely due to the fact that the blacklegged tick, also known as the deer tick, which is the vector for the Lyme disease pathogen, has been increasing in its abundance and in its spatial distribution within Michigan. And that's not unlike other places in the US, but in Michigan, actually, there have been many tick species here already, but the most prevalent one is the American dog tick. And that's been around, and it's been around in the Upper Peninsula and in the Lower Peninsula, but in the late or mid '80s, 1980s, the blacklegged tick was first discovered in Menominee County in the UP. And then, since that time, it's been spreading somewhat in the UP, but then sometime in the early 2000s, it was detected, the same tick, in southwestern Michigan. And then over that time, it's just been spreading.

It may have been here in low numbers before in the Lower Peninsula in the late '90s or in early 2000s, but certainly something then changed and its abundance just grew. And we first saw it really, as far as ticks go, racing up the lakeshore of Lake Michigan in those coastal dune forests, and students in my lab had studied, beginning in 2004, and actually Eric Foster, who was at the Michigan Department of Health and Human Services, actually, he started studying this with Ned Walker and other folks at the Michigan DNR, including Steve Schmidt at the time, who was the state veterinarian at the time, they had looked at blacklegged ticks on hunter harvested deer in the early 2000s. And they saw that there were some more ticks in southwestern Michigan.

And then, when my student Sarah Hamer came, she was working with Dr. Graham Hickling, who used to be here with me also, and we saw the tick progressing up the Lake Michigan lakeshore up from southwest Michigan up to Sleeping Bear Dunes in a matter of, I would say, six, seven years. And the numbers just have increased. And now, certainly, the ticks have spread inland a bit, and Lansing is a little bit of a hotbed in certain areas for the blacklegged tick. And they've actually reached over to the Lake Huron shoreline, but the distribution's still patchy. Some areas in the state, we still have a very hard time finding the blacklegged tick, but in other areas, I think a lot of people, including yourself, have been noticing more ticks. And then on top of that, unfortunately, not as much has been studied really carefully looking at the changes in the American dog tick numbers. But from what I understand, talking to people like Dan O'Brien and others who spend lots of time outdoors, it seems that the dog tick has been increasing in abundance as well. Even though it's widespread, the numbers seem to be increasing more.

Holly:

That's the one I see most often. When I find a tick on me, it's usually a dog tick. You've talked a little bit about blacklegged ticks and the dog tick. Can you explain maybe the differences between those and any other tick species that might be found here in Michigan?

Jean:

Yeah. Well, here in Michigan, as you were just saying, the American dog tick is the most commonly found tick by people and their companion animals. And we know that from data that of tick submissions to the state health department, as well as my graduate student has been looking at pictures received by the public through the Tick App, and then also, in her work looking at ticks that are presented on dogs from veterinarians. The American dog tick is the most prevalent, then it's the blacklegged tick, and then, from time to time, we also get on dogs and people this tick called the woodshop tick, which is in the same family as the blacklegged tick. And then there are a few others that are much less commonly run into by people and companion animals.

The differences are, well, visually, they look different, but also, they're different because they, from a human health standpoint and animal health standpoint, they transmit different pathogens. The American dog tick transmits, is most well known for transmitting the Rocky Mountain spotted fever and other bacteria in the spotted fever group, and which can, they can cause people to feel like they have the flu and such, and Rocky Mountain spotted fever can be fatal. However, those pathogens are at much lower prevalence amongst the tick population, so we rarely hear about people in Michigan contracting Rocky Mountain spotted fever, although it happens every few years. And then we hear some press releases to remind people that, beware of this. You still have to be aware of this tick causing problems, even though many of us have picked them off of us in the field.

The American dog tick in our areas, up here in the Midwest, is often known as the wood tick, so that's very important to get across. These are the two names for the same species. And I should say, as a visual, I heard this from Selma. I thought it was great that usually, they're these larger brown ticks, but the female adult tick, and they come in male and female forms, she has this little creamy coloring that sometimes people call a necklace on her top side. And then the males, however, have more of this, they have a coloration pattern that extends their whole body. Some people call it looking more like golden pinstripes, so little white to differentiate the male and female dog tick.

Holly:

Necklace and pinstripes.

Jean:

That's right, versus some others. Yeah, right. Then the blacklegged tick, or also, AKA, its other name is the deer tick is the one that transmits the Lyme disease pathogen, Borrelia burgdorferi. And there are multiple stages that people can encounter. The adult stage, and so the female tick, she has this red cover. Her body looks mostly red and she has a little black shield. And then the male is just pretty much all dark brown and black. And they are the size, they say the male is the size of a sesame seed, and the female's a little larger. And then the nymphal stage, where we call the teenage stage, is pretty much, it's the size of a poppy seed.

Holly:

That's tiny.

Jean:

Yes, of a little poppy seed with legs, eight legs, and more dark coloring. And then the larval stage, where people hardly ever see, people might call them seed ticks if they come across them and a whole bunch come on them, but those are little, they have six legs, and they're even smaller.

Holly:

You've talked a little bit about some of the human health risks that are associated with ticks. Let's dive a little deeper into the Lyme disease concern with blacklegged ticks. And there is a connection with deer and mice and blacklegged ticks. What is that connection and what is the relationship there?

Jean:

The blacklegged tick has four life stages. It's got the egg stage, then it's got the larval stage, which has six legs, the nymphs, which have eight legs, and then the adults, which come morphologically, you could actually see males and females. Ticks are obligate parasites, they have to get a blood meal at every stage. The larva is going to be looking for a host. And these ticks also, they don't run after anyone and they don't fly and they don't drop from trees.

Dan:

They don't drop out of trees. [inaudible 00:22:31].

Jean:

That's right. The mom lays the eggs in one clutch, something like 500 to 2,000 eggs at one time. Then the larvae emerge, they hatch out of their eggs, and they are hungry and they're looking for a host. They will wave their front pair of legs in this term, we call questing, questing for a host, and because ticks don't have antennae, but they have little organs at the tip of their front pair of legs, right under their claws, and they wave them in the air, and they sense things like heat, passage of light, maybe some carbon dioxide that hosts might emanate. And then, so when a host comes by, they also feel vibrations, and they may attach. Then they'll attach to a host and there can be many different species of hosts that larvae feed on. People have counted maybe 100, 150, it depends. They're generalist ticks, parasites, so they will feed on small mammals, mice, voles, shrews, they'll feed on birds, any that forage on the ground, so robins, catbirds.

Dan:

Ovenbirds.

Jean:

Ovenbirds, yes. And in certain places, if they exist, they will feed on lizards as well. I actually, we saw a great picture from one of our summer workers from Port Crescent State Park that was of a five-lined skink, so they will feed on five-lined skinks, they love skinks. And they will then definitely feed on medium sized and large sized mammals, so raccoons, possum, skunks, squirrels, and then whitetail deer, as well as bear, et cetera. The larvae can feed on all of these, but they tend to feed mostly on probably the small mammals, in part because the small mammals are so numerous and in their habitat, running around in our woods here.

Dan:

Just more likely, basically, that they'll run into a rodent than a lot of other things.

Jean:

Right. And then, what happens is they take their blood meal, they're on the host for about three, four days, takes them that long to suck enough blood to be fully engorged, and larvae are born without the infection. At that point, if the host is infected, they will suck in the pathogens, these spirochetes that cause Lyme disease. Then what'll happen is when these larvae, when they finish feeding, they'll detach on the host, drop into the leaf litter, and they will undergo development and molt into the nymphal stage. They'll grow another pair of legs, they'll be a little bigger. And if they were infected in their larval blood meal, they'll then be infected as unfed nymphs, hungry to get on another host.

And then, when a host passed by, and again, all the same types of hosts these nymphs would be feeding on just like they had as larvae. Then, if it's a host species that actually can get infected with the Lyme disease pathogen, because not all hosts can, then the nymph will transmit that pathogen to the host. And then that host will become infected and be able to pass it back to any other larvae or nymphs that feed on it. If the nymph then, let's say so after it finishes feeding, it's infected, it drops into the leaf litter to molt into the adult. When it comes out as a male or a female, it will be infected, but the female and the male, what happens next? They need a blood meal, but they also need to find each other and mate. That's the job of the adult tick.

What they do, again, unlike mosquitoes, they don't fly around and they don't do massive migrations to find a host and find each other. What happens is they just wait and they queue to a large host. And in our ecosystems, the most abundant large host is the whitetail deer. When they do that, they get on a host, then they're actually able to get their blood meal, and they're probably going to be likely to find their mate. I often say in my classes, it's just like when people want to find each other, a partner or spouse, instead of going out just randomly, they go to a bar, something like that, coffee shop, bar, whatever is here.

Dan:

Right, so the deer is like a tick bar.

Jean:

Exactly. And for audiences who might remember, I think of it as a tick Love Boat.

Holly:

There you go.

Dan:

More romantic.

Jean:

Right, and it's cruising around in the woods. But the thing is, in terms of infection, the deer aren't competent hosts. They cannot be host for the pathogen, I should say. They're great hosts for the adult ticks. And the female takes the large blood meal, and once she's mated, then she's able to drop off and then lay her eggs, and then she dies, unfortunately. But then the deer does not become infected, so it can't ever transmit this pathogen to any other subsequently feeding ticks, but also what happens then it's then the whole life cycle of the pathogen comes to screeching halt because the female does not pass her pathogen on, the Lyme disease spirochetes on to the baby ticks. That's why when the baby ticks are born, they're uninfected. Ticks don't transmit the pathogen on to future generations of ticks and the hosts don't pass on the infection to their progeny. It has to be this tag team dynamic.

Dan:

Right, which is interesting to me because they even have the name, the deer tick, so a lot of people think that deer play a big role in transmission of Lyme disease. But essentially what you're saying is that other than just being a sort of meeting place for the ticks and a place for them to get a blood meal, they actually cut off the infection rather than act as a source of Lyme disease for more ticks

Jean:

That's right. Actually, you see, in some areas, they've seen some research in Sweden and others, the more deer you have, the lower the proportion of tick that are infected.

Dan:

Which is really interesting because I think most of our listeners will think the opposite. Again, because the tick is called a deer tick, people think where you have really abundant populations of whitetail deer, you're going to have a lot of Lyme disease, but that isn't necessarily the case.

Jean:

But what happens is when you have more deer, you have more ticks. Proportionately, they're less infected, but number-wise, you may have more infected ticks. Then your listeners, they might say, "Ah, maybe I was right."

Dan:

There you go.

Jean:

It would be more infected ticks. But the relationship is a little more complex than that, so you can't always predict how much Lyme disease in the tick population there will be just based on the deer population. But there are other hosts out there that vary in how well they can host the tick and the pathogen so the host community of wildlife really plays a strong role, large role in contributing to what proportion of ticks are infected in a given area.

Dan:

Jean, you spoke earlier about the emergence of ticks along the west coast of Michigan from where they were, say, 20 to 30 years ago. What's the transport mechanism? Is it movements of these ticks on deer? Are the deer transport hosts or do they move on birds or both?

Jean:

Yeah, both. Ticks, again, they can't fly, they crawl a limited distance. All of their dispersal is based on the hosts they feed, so on the backs of furry hosts, scaly hosts, or on the feathers of winged animals. The actual spread up the coast in the manner that it did, which was very gradual and it seemed very much continuous, that suggests to me that most of the spread was probably just by one community of hosts each year just spreading their ticks, moving them up northwards in their normal dispersal patterns. Every animal population, once it has their babies, babies usually have to, as juveniles, disperse somewhat because there aren't enough resources, either food or homes, for that population, so to reduce competition, they usually move.

I think just some of that movement, and that could still be some movement for any of these hosts that host the ticks, but certainly perhaps with the deer, then they can move a little further depending on what deer movement is like in that area, but certainly little rodents and such. Sometimes people think about, wow, that distance, probably birds, maybe through migration, they would be spreading. And that's definitely possible, but then we have to think about when birds would pick up ticks and when they would actually be dispersing, would they actually be spreading them in their breeding period when the fledglings are moving, or is it in the fall when they are migrant, and spring when they're migrating, in this case, the spring for moving northwards. But then we need to talk to the ornithologists more to see how much of that migration bringing ticks somewhere, like for instance, the southern US or southwest Michigan, what would be more likely for them to be spreading ticks gradually off the coast?

In some ways I think if birds were more involved, it may look more like... Not shotgun, certainly, because birds, they will migrate in certain areas going to riverine ways or other ... They'll have preferred places to go. But if they were actually spreading ticks a lot more, we may see little, I would think bull's eyes or little bombs, maybe, in different areas. And they may be more patchy in how they disperse the ticks as opposed to this gradual, continuous movement off the lakeshore. But having said that, I bet there could be certainly little areas that are receiving ticks from birds. That might be a reason why we see some more of the spread of the blacklegged tick, certainly in some of these other far outlying areas, like the coast of Lake Huron, but yet, not so much in that I-75 corridor from Midland up to the bridge. We don't seem to be seeing as many ticks there, although deer populations, small mammal populations, would be just as abundant there.

Dan:

It isn't just the abundance of the hosts for the tick either.

Jean:

Yeah. And the habitats, so one of the reasons why we think the coast has been good for the ticks as a first initial place was that perhaps they came down and around the lakeshore from Wisconsin through, took them a while to get through Chicago and then Indiana. But once they got here, they had these coastal forests, and researchers have found that perhaps sandy soils might be a very good type of a substrate, it might be very good habitat there.

Rachel:

We've talked a little bit about Lyme disease and Rocky Mountain spotted fever. What are some other dangers that might expose to people?

Megan:

The deer tick or the blacklegged tick can also transmit a disease called anaplasmosis, which has signs that are similar to Lyme disease in humans. And both Lyme disease and anaplasmosis can be transmitted to your family dog as well as to the rest of the members of your family. And in some cases, Lyme disease can also be transmitted to your horses. The blacklegged tick or deer tick can pose that additional danger to the other members of your family. We have another very rare tick that we see sometimes in Michigan called the lone star tick, and a lot of times, this tick is familiar to people because the adult female has this really bright, iridescent white spot on her back and she's absolutely gorgeous. But unfortunately, lone star ticks have been linked to what has been called a meat allergy. There's a compound in the tick's saliva when these ticks bite called alpha-gal that can cause a hypersensitivity reaction or an allergy, and some people who are predisposed to it, that causes them to have an allergic reaction to red meat. And that includes bacon, for all of those who enjoy eating bacon.

Dan:

Not bacon! Anything but that.

Megan:

That's usually the response I get, "Not the bacon!" Unfortunately, these people get bitten by a tick, and then hours later, after they've eaten a meal that consists of some sort of red meat, they'll have this hypersensitivity reaction, and they don't know why. They just wake up in the middle of the night having a severe allergic reaction, and they have to go to the hospital for this. That's something to keep in mind. We haven't seen a lot of instances of the lone star tick in Michigan, and we certainly don't think that it's firmly established in any great numbers in Michigan yet, but we do see handfuls of ticks that are submitted through the tick submission program with the state health department as well as through the Tick App, where we get pictures of ticks sent into us.

Rachel:

What are some types of ways that people could prevent potential tick bites?

Megan:

There are a couple of different strategies that you can use to prevent tick bites. The very first strategy is to just prevent ticks from getting on you in the first place. That includes when you go out into an area that could contain tick habitat, and that changes, depending on the type of tick that you're talking about, we recommend that you wear an EPA-approved tick repellent. This includes DEET, keratin, lemon oil of eucalyptus, those type of products. We usually recommend that the active ingredient in that product is at least 20 percent. That includes most of the mosquito repellents that you find in your local store. We also recommend that you go out in long sleeves and long pants. Now, with the type of weather that we see in Michigan in July and August, that could be really difficult, but we recommend that you tuck your pants into your socks and wear tall boots if you can.

In addition, there's a product called permethrin that is not to be used on your skin like DEET or picaridin, but can be used to treat your clothing. And this will actually kill and repel ticks that get onto your clothing as you're walking through tick habitat. Those strategies will help you to repel any ticks that get on you while you're out in tick habitat. We also recommend that while you're in tick habitats, stay on groomed trails. Once you've gone out into the forest, you've come home, and you've done everything that you could to prevent getting ticks on yourself, we recommend that you take a shower within two hours of coming home. Not that you're necessarily going to wash the ticks off, but this will give you an opportunity to do a really thorough tick check on any parts of your body that are protected, they're nice and humid, and you're not going to just brush them off, so we're thinking behind your knees, in the groin area, along the waistband and your armpits, around the bra strap area for women, and then behind your ears and up into your hair.

Dan:

Megan, let's say one of our listeners finds a tick, then is there a correct way that you can remove those ticks? Because there's a lot of stuff out there on the internet, some of which looks pretty sketchy.

Megan:

I know that there's a lot of advice out there that you should cover it with Vaseline or you should burn it off or you should use alcohol on it to suffocate the tick. Don't do any of that. Because there is a threshold of time during which transmission of certain pathogens can happen, you really want to get the ticks off as fast as you possibly can and let them blood feed for as little time as possible. We recommend that you take tweezers, the pointier the tweezers, the better, so we do recommend that you go to the hardware store and get some fine tip tweezers. They're pretty easy to find. And you want to grasp the tick as close to the skin as possible. You don't want to squeeze the tick in the middle of the body because then you're squeezing tick guts into your cut.

You want to grasp it as close to the skin as possible. If you get a little of your skin along with the tick, you're just doing a really thorough job. You want to grasp that tick and pull straight up and out. It might take a little bit of force to get the tick out because they do cement themselves into your body, but you just pull that sucker out. You don't have to twist, you don't have to do anything fancy, just pull it out. And then we recommend that you save your tick. Don't flush it down the toilet, don't squish it and put it in the garbage. We recommend that you put it in a Ziploc bag with a moist paper towel or cotton ball, and you can put that in your refrigerator. That way, if you do become sick within, say, a month's time, you can take that tick to your doctor, and that will give them a little bit more of an idea of what illnesses they may be dealing with, since not all ticks transmit the same pathogens. We also recommend that you take a photo of it and send it either to the Tick App or to the Michigan State Health Department's photo submission. And then you can also submit your actual tick if, it's still alive, to the Michigan Department of Health and Human Services, where they have a tick identification and testing program.

Rachel:

What about ticks getting on your pets? Are there any prevention protocols or anything you can do to help keep your pet safe from ticks?

Megan:

Oh, absolutely.

Jean:

And that's really important because also pets can present a risk to the family for ticks.

Megan:

Yeah. I always recommend that you contact your veterinarian and get a good tick prevention product from them. There are a lot of different products on the market that will also work against fleas as well, and nobody wants those in their house.

Holly:

We've been hearing a lot about this new Tick App. Dr. Porter, would you be able to tell us a little bit more about what it is and what do you hope to learn from it?

Megan:

Absolutely. The Tick App is a mobile health application or app that was designed by researchers at Michigan State University, at the University of Wisconsin, Madison, and Columbia University to identify the behaviors that bring people in contact with ticks. Because we talked earlier that the main way that we have to prevent tickborne disease is by just not contacting ticks in the first place. Unfortunately, we don't have a lot of research, especially in the Midwest, to tell us where people are contacting their ticks. The point of the Tick App was to ask people where are they contacting ticks and what are they doing in their everyday lives when they're contacting these ticks to help us identify and narrow down our prevention messages so that we can really target those behaviors and help people to do the best job to avoid ticks in the first place, and then to prevent ever developing a tickborne disease.

Holly:

How can people participate or submit their tick data to the app?

Megan:

The Tick App is available through the Apple App Store as well as through Android app stores as well. And then there's also a website where they can go and find places where they can download the app as well.

Holly:

Okay, great. And we'll be sure to include links in our show notes for folks so they can find it pretty easily. Well, thank you so much for your time. We really appreciate it. Thank you, Dr. O'Brien, Dr. Tsao, and Dr. Porter. 

Announcer:

Michigan.gov/DNR trails is your destination for trail maps, trail etiquette, and trail closure information, trail information for biking, cross-country skiing, horseback riding, hiking, off-road vehicle riding, snowmobiling, snowshoeing, and even water trails for kayaking and canoeing are available. While you're there, remember to check out information about pet friendly recreation track chairs and the Iron Bell Trail, all available at michigan.gov/DNRtrails.

Rachell:

Now is your opportunity to win a wild talk podcast camp mug as a thank you to our listeners will be giving away a mug or to every episode. Our May mug winners are Richard Schulz and Madeleine Smeltzer. Congratulations, Richard and Madeleine and check your emails will be getting in touch with you soon. They answered the question What is a group of turkeys called? They are called a rafter. Now to be entered into the drawing this month, test your wildlife knowledge and answer our wildlife quiz question this month. Question is what Michigan bird species has an upside down brain? All right. After you've thought about that, email your name and answer to us at dnr-wildlife@michigan.gov. To be answered for a chance to win a mug. Be sure to include the subject line is mug me and be sure to submit your answer by June 15th. Good luck, everyone. 

Announcer:

Michigan Conservation Officers are working hard to protect and keep the outdoors safe for current and future generations. If you witness a natural resources violation, you can call or text the report, all poaching hotline, 24 hours a day at 1 800-292-7800, or fill out the complaint form available@michigan.gov/rap. If you would like more information on becoming a conservation officer, click on Become a CO at michigan.gov/conservation officers.

Racel:

Well, thanks for joining us. Remember, if you have any questions about wildlife or hunting, you can call 517-284-WILD or email dnr-wildlife@michigan.gov. 

Announcer:

This has been the Wild Talk Podcast, your monthly podcast airing the first of each month in offering insights into the world of wildlife across the state of Michigan. You can reach the Wildlife Division at 517-284-9453 or DNR-wildlife@michigan.gov.