Dr. Rich has been a Professor of Microbiology at the University of Massachusetts since 2005. He served as Department Head in Plant, Soil and Insect Sciences (2009-2013), Director UMass Genomics Resource Laboratory (2006-2015), and is founding director of the Laboratory of Medical Zoology (2005-present). He has an M.S. from the University of Vermont (1993) and began conducting research on transmission of vector borne zoonotic diseases continuing his graduate studies at the Harvard School of Public Health. He received his PhD from the University of California (1997), followed by a postdoctoral fellowship at the University of Rochester (1998), followed by his first faculty appointment at Tuft s University School of Veterinary Medicine (1999-2005). His work centers on zoonotic disease transmission and intervention with particular focus on human malaria and tick-borne diseases, including Lyme borreliosis.
Transcript of Episode 11: Tick Testing With Dr. Stephen Rich
Cindy: Hi everybody out there. Doug and I did another road trip today. We’re up at UMass, Amherst in Massachusetts, and we’re meeting with Professor Stephen Rich. And he is part of the microbiology area. His primary interest in zoonotic diseases is those that are vector born. And for all those people that don’t know what that it is … it’s a blood feeding transmission from ticks and mosquitoes.
He’s the director of the laboratory of medical zoology, and it’s very important because it performs testing of ticks for lime disease and co-infections; and this can be very important in the treatment for people that have had a tick on them and it can be sent up here to the lab. So welcome. Welcome Professor Rich. Give me some information about you and this lab that is so very important.
Professor Rich: Thanks very much for having me come today. We work on what we’ve been doing for the last 25 plus years is studying diseases that are, what you say, vector born. They are also unique among diseases that are, what we say, zoonotic is the fancy term for it.
What makes Lyme disease tough to understand and tough to study is that it is not inherently a disease of people or didn’t start out that way. It’s a disease that’s in wild animals and then it spills over into us. That’s what’s meant by [00:01:32], so anything we do to sort of combat it in ourselves doesn’t necessarily impact on the source of that, which is the ticks and the mice that live out in the wild. A lot of my focus has been looking at ticks in the wild and the diseases that they transmit in those wild populations; and then, how they spill over into us.
I have been doing that since I was a graduate student in Harvard several decades ago now.
Cindy: Don’t date yourself.
Professor Rich: Yeah, no I won’t.
Cindy: He looks very young to me for all you listeners.
Professor Rich: So we’ve been doing that for a long time, and several years ago … eleven years ago now, we decided that we had accumulated some tools and some information that we thought was not only useful to the scientific community in increasing our understanding of those zoonotic scientific cycles of those wild populations but really could be brought to bear on the folks that are being exposed to these pathogens. So what we did eleven years ago was we sort of opened the lavatory up, and we started providing some of the tools that we had developed to the general public. The tools in particular were … we had the ability through the miracle of modern molecule biology to detect the presence or absence of pathogens so that things that caused Lyme disease, Babesia, and Anaplasmosis in humans. We had the ability to find out if those ticks possessed or didn’t possess those individual pathogens.
Our opening of that service was to say, “We can offer this to anyone that has been bitten by a tick. We can test your tick and tell whether it’s positive or negative for those pathogens”.
Cindy: What’s the turn around time?
Professor Rich: When we started doing it, it would take us about a week. Many of the other services that’ve evolved since maybe take two weeks sometimes they take up to five or six weeks. We’ve actually perfected our procedure down to the point where we now deliver things in three business days or less. So when we get really busy in May and getting hundreds of ticks per day, it takes us three days to turn the results around from the day they cross our threshold. At this time of year when things are slower, we can give results in 24 hours.
When we started doing this, we knew that we were helping people to understand where the diseased were. So there are bigger problems in some parts of the state of Massachusetts compare to others, but what we didn’t realize–and we’ve only come to realize–is that we are also giving individuals information about their individual exposure. We can tell people really quickly some of the earliest information about those tick disease exposures. And I’ll emphasize at the beginning Cindy that this isn’t a diagnosis. We don’t expect that people are going to come and test their tick and have information about whether they have disease or not. What they are going to get is whether they were exposed or not. And that’s a big piece of the puzzle. It’s not the “whole enchilada” if you will, but it is a big piece of the understanding of the exposures.
Cindy: In terms of the amount of exposure experience and what not with this tick lab, how often are you finding that these ticks are infected? And I know you just said that different areas have a higher prevalence, but overall are the ticks coming from different states etcetera or primarily just Massachusetts?
Professor Rich: We receive ticks from all 50 states actually …
Cindy: You do?
Professor Rich: Even Hawaii, although the Hawaiian ticks came from someone that visited the Northeast and acquired their ticks here.
Cindy: And they brought them on their person, on their luggage, how did they get them there?
Professor Rich: All of the above. Sometimes it’s on their person. Sometimes it’s on their pet. Sometimes it’s in the laundry that they brought back from a trip, whatever.
Cindy: Oh my God. That’s crazy.
Professor Rich: So they all get sent to us. And yes, we see differences and in infection rates. We difference in different types of species of ticks, different parts of the country. We see different times of year have different incidence of disease. And we see different pathogens in different ticks.
Cindy: So it’s very variable.
Professor Rich: It’s highly variable, and it’s information that people want to know. They want to know what they’ve been exposed to, so we’ve been able to start to help people to sort that out.
Cindy: In terms of the life span and the newer ticks … and those I believe are nymphs, correct? Or am I wrong?
Professor Rich: The very youngest ticks are the larval ticks.
Professor Rich: Ticks are interesting. They are a little bit different from mosquitoes. People probably know more about mosquitoes because we encounter them more frequently. A mosquito can feed on me, and then it can go and feed on you, and then it can feed on all of us, and take a turn. Ticks don’t do things that way. They take a single blood meal, and they maintain this very long intimate relationship with the thing they’re feeding on. And they’ll stay on for sometimes several days … sometimes a week. And so there’s one opportunity at each life stage to take blood and/or to transmit pathogens.
The first of those stages is the larval, and then nymphal stage, and then the adult stage. So three times in the course of a tick’s [inaudiable 00:06:44].
Cindy: And I understand that it requires a blood meal to move on to the next stage of their life.
Professor Rich: Yep, that’s a very good point. So they use all of that blood basically to molt and go to their next phase.
Cindy: What happens after their blood meal and they’re like, “Yay, I’m full.” How is it possible that we’re getting these infections if their taking blood out of us? I know there is another step that occurs, and I wonder if you would explain that?
Professor Rich: So when ticks feed they take things in and they push things out. So it’s sort of a regurgitation process.
Cindy: Why do they do that?
Professor Rich: Well, imagine that they have to stay on you for a week to feed.
Professor Rich: And they have to kind of go unbeknownst to you, so they are spiting things in from their salivary glands that sort of dumb down the immune system so that you don’t have a strong response or you’re not itching there. So they need all these chemistries to sort of do their whole blood feeding process. They’re also taking enormous blood meals. Again, compared to mosquitoes, it’s a gigantic blood meal. Several hundred fold times more than their own body weight. And they do that by concentrating that blood and excreting the water out[crosstalk 00:08:12]
Cindy: Oh that’s where that comes from
Professor Rich: Yep, so they make it really concentrated, and then they slurp it up at the end. And that’s their meal.
Cindy: Oh that’s crazy. We should use a lot of them when we centra fuse and do blood for transfusion. That might be a new way we can utilize ticks, I think. Instead of using the machinery like electricity, you know. No, alright, nevermind.
Professor Rich: That’s an optimistic view.
Cindy: That’s very us. You know, these things happen. What do you find in terms of ticks and percentages of co-infections? Are you seeing equal amounts of Lyme with co-infections, or are you finding more ticks per se that just carry the Lyme?
Professor Rich: By in large, the most predominant pathogen. I use the fancy word “pathogen” so that applies to all the different microbes that are inside ticks that cause disease. But the most common pathogen is the Lyme disease pathogen in ticks. So wherever there’s a deer tick–and that’s true Wisconsin, or Minnesota, or Massachusetts, or Virginia–we see about 50% of the adult ticks are infected with the pathogen that causes Lyme disease. About 30% of the nymphs and very small number of the larvae. We can talk about why that is in a second.
To compare the other things that are also called co-infections, which I think is a little bit misleading because they’re actually just separate pathogens that get transmitted in their own pathways. But things like Anaplasma and Babesia are much less frequent, much lower in incidence. Babesia is probably at its height in around 8-10%, Anaplasma is maybe 5%, newer pathogens like Borrelia and Emmerdale, probably closer to 2%, and Powassan virus, probably less than 1%. So we test all those pathogens. And one of the reasons that we think it’s useful is to provide that information is most Docs in the Lyme endemic areas know the incidence of infection in deer ticks for Lyme disease. They don’t so much know it for Powassan or Anaplasma or Borrelia or Emmerdale or Babesia, these so called co-infections.
So we’re really helping to both raise the awareness of individuals that’ve bitten by ticks, but also we’re hoping that the people in the medical communities … that their awareness is raised by what their patients are being exposed to.
Cindy: Do you send information out to primary cares or infectious disease people routinely, or are they requesting information from you?
Professor Rich: We call Tick Report. That’s the service we provide. And Tick Report is really just bootstrapped almost by word of mouth. Initially, we started it through our extension service, which is the same folks that do excellent work in the state testing plans for present absence of pathogens. And we just put it on a webpage and we just made people aware that we were offering this service. And it’s grown over time. We do some outreach now on Facebook. We do some radio stories. So now, it’s getting to the medical community so that we don’t communicate this directly with them. Many docs will send us ticks from their patients because they want to know, and it helps the conversation between the patient and the physician to say, “Here is a tick it had XY and Z. I was exposed to this. The tick fed for a sufficient period of time because that’s an important factor in this.
Cindy: And you can tell how long it fed based on your study?
Professor Rich: To degree of error, yes. We can’t tell if it’s unfed, partially fed, or whether it’s fully fed. And if a tick is unfed, even if it’s infected, it posses very little risk for most pathogens. But again, that differs from pathogen to pathogen. So things like Powassan virus are thought to be transmitted maybe in only 15 minutes of feeding. Where as Lyme pathogens would be 24 or even 48 hours before you really have an increased probability of that transmission.
Cindy: That’s where the information comes where some of the people said well if you were out two days ago you’re not going to get that. But you can’t be 100%. I mean are some better suckers than others? I guess you don’t know.
Professor Rich: You raise another good point. One of the things that we learned as we went along, so we’re scientists… I’m a scientist. And scientists talk geeky to other scientists. So we said things like 95% of the probability of blah blah. And we learned that in communicating with the public that didn’t always register the way we understood it to be. So for example, when I say that most tics take at least 24 hours to transmit the pathogens of Lyme disease, people that are listening will say, “Wait a minute, I got Lyme disease and my tick only fed for 12 hours”. It’s important to understand that these are all averages. These are all looked at over different studies. We modify these numbers as time goes on, so we collect more data. And that’s one of the reasons that we think people value what we’re doing because we’re giving you information about the tick that fed on you.
And we can tell you, within boundaries, what the risk is to you based on that tick bite.
Cindy: This is fairly accurate, your testing.
Professor Rich: This is highly accurate. Without going into the details of the clinical testing, a lot of people talk about the short comings of clinical testing, the ability to detect pathogens in yourself or exposure to pathogens. And people say, “Oh, the testing is really lousy.” Our testing, because it is inherently different, is much more accurate and much more reliable because we’re not looking–as we do in a blood sample–for indictions of antibodies that tell you whether you’re exposed or whether your sick. We’re actually using the same methods that they use to pull DNA out of mummies or wooly mammoths that are tens of thousands years old. We detect the pathogen DNA, and we can do that down to just a couple of molecules with a very high degree of accuracy.
The next question would be, “Why don’t we do that in people?” Well, the reason is that we can take a whole tick; we smash it up. We pulverize that tick, and we take every … yeah it’s very gratefying … um [crosstalk 00:14:49]
Cindy: (shooting sounds and laughing)
Professor Rich: We could show you down stairs how we do it.
Cindy: I’d like to.
Professor Rich: And then we take all that and we detect those tiny needles in a haystack. That little pieces of DNA and the whole tick, and we can detect all of them. Well, obviously we wouldn’t want to do that for a human patient. Where we take a whole patient and grind them down just to distract DNA. So that’s one of the reasons why we can do much better on ticks than we can do on people.
Cindy: How did one find out the transmission time? Was that tested on mice? How did we know how long it takes to transmit possibly diseases?
Professor Rich: Most of those studies, and they’re numerous, were done with mice. So you take mice and you know they’re infected, or if you take some of the mice, or lavatory rats or rabbits or whatever else, and you see the rates in which the infection gets acquired by the ticks. And then you can do a times series and you can look back. And you can say, “This many got infected in 12 hours. This many in 24 and 48 and etc.” The next thing that we know is that does not necessarily apply to what happens in human situations. So again, in addition to being able to give people accurate information about what’s going on with them, we can look at all of the data in aggregate. And we can start to look at the outcomes of the people that’ve been bitten by ticks for 48 or 36 or 72 hours, and we can say, “What were the outcomes of those? How many of those people ended up getting full blown cases of Lyme disease or Babesia or Anaplasma?
Cindy: Now I just want to clarify when you talked about the testing on the mice. I think you said their infected, but I think you meant you know they’re not infected and then you put on the infected tick. Is that what you meant?
Professor Rich: Well…
Cindy: Because you have to clean mouse to determine when it gets infected with the Lyme.
Professor Rich: Yeah, so you do the experiment both ways because you can see the rate at which the infection gets picked up by the tick from an infected mouse into an uninfected tick and vice a versa.
Cindy: Oh I see. Okay, right because these ticks come out into the world uninfected.
Professor Rich: That’s right, yeah
Cindy: And they still want to know why are mice not killing over from being ill or having this disease in them, or why deer dragging a limb. What do they have that kind of their the host and not so much infected that we can’t get? I’m just wondering if we’re going to figure that out.
Professor Rich: Well, I can’t tell you what the factor is, but I can tell you that cause is evolution. These organisms, the mice and the deer, have evolved with these pathogens. So they’ve been exposed to them through the eons of their own evoluion. And they’ve developed sort of a happy equilibrium between the those species and the Borrelia, so they’re not getting sick as much.
Cindy: That’s crazy. We need to figure that out. Before we end here, this has been extremely informative and I think a lot of questions have come up and you’ve discussed them. And we have to discuss the importance of getting these ticks, sending them in. And I have read that you can send them in alive; you can send them in dead. You don’t care because you’re going to take them and pound them to smithereens before doing testing. So I really want to thank you, but I do have a couple of questions.
Professor Rich: Sure.
Cindy: I really want to know what ticks you off.
Professor Rich: Well, if we’re talking about ticks and Lyme disease, there are two things that tick me off:
Cindy: Well I don’t know if we have time for two, but give me. No, you can! Give it to us.
Professor Rich: I’ll just go with one if you need. But I get frustrated in this realm when people instill fear with people with ticks because I don’t think people ever make smart decisions when they’re afraid. So what we really think our job is to not scare people, but to educate people. So I get a little frustrated when people instill fear. Sure there’s reason for concern. An example I always use is, “When I was a kid we never thought about going out and getting sun burn and all that stuff. We know better practices. We know that we put sunscreen on when we go out on all of our bodies that are now exposed. We know how to be safe and so I don’t have to be afraid of the sun. I’m respectful of the fact that I have concerns about going out in the sun. Same with ticks and Lyme disease. Don’t scare people. Don’t make people think that there’s nothing they can do because people just aren’t going to make the right decisions. They’re going to be sitting at home frightened and afraid to go out of their houses. That’s one of the things that really ticks me off.
Cindy: Alright. What’s two?
Professor Rich: Well, you told me I could do one, so I forgot the second one.
Cindy: Alright, well if you…
Professor Rich: I guess the other one is to just make sure that scientist, those that are collecting this information, that we figure out a way to make clear to folks in a language that is clear to folks. If we don’t communicate the information that we’re collecting in a very concise but clear way, then we’re spending other people’s money for all the wrong things.
Cindy: Alright. Question 2 is that in life, people are given lemons. And, I guess the lemon situation for me is that people are given Lyme disease, but the lemonade is providing this information in education; so people can clearly understand what they’re dealing with and be advocates for themselves. So in life, you must have gotten a lemon somewhere. I hope it wasn’t a car, but tell me what your lemonade is.
Professor Rich: What is my lemonade? Wow that’s um
Cindy: Well, what’s been gratifying to you?
Professor Rich: What’s been gratifying is being able to have a career that you can make a difference; you can impact people’s lives both in this tick report stuff. I really enjoy working with students. I enjoy working with my colleagues. I like being part of something where we feel like we’re making things better in the world.
Cindy: I get that, so can I get an honorary degree from your lab? You can give me one of those caps and I’m just anxious
Professor Rich: I even have a cap and gown in the [inaudible 00:21:26]
Cindy: You do! Oh, too bad this is not video. Well to all of you that are listening out there, this is Cindy Kennedy. And you’ve been listening to, “Living with Lyme” and we encourage you to come back to another episode and learn some more. Have a great day and make it the best you can. Take care now. Bye bye.