Short Talks From the Hill, a podcast from the University of Arkansas, highlights research and scholarly work across campus. Each segment features a university researcher discussing his or her work.
Camilla Shumaker: Hi, welcome to Short Talks From the Hill, a podcast from the University of Arkansas. I’m Camilla Shumaker, and I’m here with Ashley Dowling, associate professor of entomology, and today we’re going to be talking about chiggers and ticks. I noticed on your website you refer to chiggers as charismatic, which is not a way I would have thought to describe them, so explain why you say that.
Ashley Dowling: Well, so chiggers are part of this this larger group of mites that collectively we often refer to as velvet mites and as… so they have three main stages of their life. We’ll start there. So the larval stage is what hatches out of the egg, is what we refer to as the chigger. They’re not so charismatic. Specifically, little orange tiny things that bite us. It’s the next two stages after… they feed as the larvae, as the chigger, and then they undergo sort of a metamorphosis. They grow, they shed their skin and they’re bigger. They come out and they’re very furry and colorful, bright red often, and that stage, which we refer to as the nymphal stage, so it’s sort of like an immature. And then the next stage, which is the adult, are both of this, furry, colorful creature that crawls around. They don’t bite people at that stage. So chiggers are really just one group of those mites, and it’s only the larvae that we refer to as chiggers. And those are the things that are basically the parasites that bite people. We’re not what they’re really looking for. They’re looking for small mice and lizards and snakes and things like that. But as most people know in this area they will happily climb on to us and take bites.
CS: I have this on-going confusion about whether chiggers stay on you after they bite; they’re in there somewhere, or if they bite you and then they leave.
AD: So this is probably a good time to say that most of what you read on the internet is probably incorrect about chiggers. There’s a lot of a lot of bad information; a lot of urban legends out there about it. So they do not burrow into our skin. When they get on us they basically make a wound in the skin. They’re not feeding on blood even, they’re just feeding on skin cells, and so they make a little wound and then they inject enzymes through saliva, which dissolves the skin cells, and then they’re basically slurping that up. And the reason they itch so badly is because with the enzymes they inject into your skin, some of those enzymes react with the skin cells to form essentially a hardened straw. So it forms this hard tube and they keep injecting enzymes in there, dissolve those skin cells then they can suck up that liquid through that tube. And so the thing is that after they’re off of you that tube is just your skin cells that have reacted to these enzymes and that stays in there, and that’s why they’ll itch for a week, two weeks, three weeks.
CS: So talk about your research on tick-borne diseases.
AD: Well I had a tick-borne disease several years back. And so I experienced that, so I knew what that was like. And I kept getting other people that would say oh yeah I’ve had a tick-borne disease or people that… and the big one, where there were a lot of people who were getting bit by ticks and then getting misdiagnosed for months by their doctors. And tick-borne diseases are really easy to treat when you catch them right away, but you let it persist in your system five, six, seven months, that’s suddenly where we end up with permanent damage. So I start looking into it and I noticed that on the CDC’s website, we were listed as the typically number one state for reported cases of spotted fever, Ehrlichiosis and tularemia. So three tick-borne diseases, and Arkansas is typically number one or number two on the list for the past five plus years, but there was no one studying that in the state. So we just decided to start surveying ticks, and so we started off where we would go out and collect and then bring them back to the lab and, through some molecular protocols, screen them for these tick-borne disease pathogens. And then I started developing a citizens science project. We created these little tick kits that had several vials in it that the people could put ticks in it when they found them, then they could mail it back to us. This last year we teamed up with Cooperative Extension around the state, so we got county extension agents in every county, we handed off a batch of tick kits to them, we had some training workshops on what to do when they’d hand out the tick kits to local residents and how to collect and how to get stuff back to us. And that worked really well so we’ve received from… last year we received about 4,500 ticks from people around the state. We’ve got a lot of ticks that we’re screening and so now we’re going through and trying to see what pathogens are there and ultimately develop maybe some sort of risk maps so we could show where the high-risk areas in the state. One main incentive of putting the tick kit together was that if we could just raise public awareness then if people felt sick in the summer, they had a fever they might think, oh, did I have a tick bite, as opposed to going to the doctor and getting treated for fifty other different things. And so it seems to be working pretty well.
CS: What are your recommendations to avoid, first of all, avoid getting chigger and tick bites, but then if you do get especially, I guess, a tick, what should you do from there?
AD: So I mean anyone who’s been outdoors in Arkansas knows you get a lot of ticks and chiggers. It’s almost impossible to completely avoid them. You can treat your clothing, which works really well, so when we’re out doing a lot of field work rather than picking off thousands of ticks, we just take the time to treat our clothing. You can treat it with these permethrin sprays. So they sell them at local stores, it’s often right there next to the bug sprays. But it will say not to put on your skin, and so you spray it on your pants; typically it’s the best place. On your shoes, your socks, your pants. For chiggers once they bite you, and as I said there’s not much you could do, you can treat the itching. They don’t vector, they don’t transmit any diseases here. In other parts of the world they do transmit some things but not here. So there’s really nothing to worry about with chiggers other than the annoying chigger bites. Ticks on the other hand, lots of diseases and so the best thing with ticks is for most of the common diseases, the ticks have to feed for an extended period of time, often 24 hours before they can actively, efficiently transmit the disease pathogen to you. And so the best thing to do with ticks is anytime you go out in the woods in the field, whatever, afterwards do a sort of methodical check of your body, looking for ticks. So if you can remove the ticks, get them off of there within a few hours, within twelve hours and then after that the next step is just to be aware. So if you do find a tick that’s been on you for a while, in the next week, two weeks, if you start feeling fatigued, if you get a fever certainly you just go to the doctor and bring it up. Mention that you had a tick bite and that you’re feeling a little off and they’ll typically just give antibiotics right away.
CS: When is the main tick season?
AD: Arkansas, it seems like always. But you know springtime once it starts to warm up, often certainly April, May is when things start to really take off. And it sort of builds throughout summer. We tend to see a decrease in ticks late in the summer when it’s hot and dry, we don’t get as many ticks. And then they’ll sort of kick back up in the fall for a little while. And so yeah, I mean, but you can still get ticks in the winter.
CS: Are you still taking ticks? Should we encourage people to send ticks?
AD: Yeah, we’re still running that project. We’ll get more tick kits out to each county extension office. We are looking to team up with landowners who might have, you know, large acreage where we could get out and actually do some intensive sampling of the ticks to see what’s there, to see what pathogens are out there. So people can always contact us if they’re willing to get involved with that. We’re looking for people that want to help out with the project.
Matt McGowan: Music for Short Talks From the Hill was written and performed by Ben Harris, guitar instructor at the University of Arkansas. For more information and additional podcasts go to kuaf.com or research frontiers.uark.edu, the home of research news at the University of Arkansas.
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