As temperatures warm across the Northeast and tick activity increases, a new study finds the blood of white-tailed deer kills the bacteria that causes Lyme disease.
The research comes from the New England Center of Excellence in Vector-Borne Diseases at UMass Amherst. The Centers for Disease Control and Prevention awarded the center $10 million in 2022 to support its work to prevent and reduce tick- and mosquito-borne diseases.
WAMC's Jim Levulis spoke with Dr. Steve Rich, the center’s executive director, about the study.
Rich: The experiment that we conducted shows that the blood of deer kills the bacterium that causes Lyme disease. And this was work done by a graduate student in my lab, it's very sound work. And it's very interesting, because what it tells us is it tells us a little bit about the natural circumstances of the Lyme bacteria and where it can exist and not exist. So we know that the natural environment for Lyme disease bacteria is in ticks and mice. Ticks get it from mice, and then they give it to other mice. And then it’s just a cycle that's perpetuated. And we've known for some time that deer are part of the cycle in that they feed ticks. But for one reason or another, they don't support the growth of the Lyme disease bacterium. And so this experiment just demonstrates that it's really something in the blood. And what that something is, is still to be decided. But it's something in the blood of deer that kills Lyme disease bacteria. And is that a cure? No. It doesn't mean that we've stumbled on a solution that people can utilize deer blood to prevent themselves from getting Lyme disease. That's not where we're proposing. But it does provide some insights, because it tells us that there's something about deer blood that kills Lyme disease bacteria. And so the next step now will be to figure out what that is. And can we use pharmacological mimics or drugs that mimic that, to induce that effect in things that we care about, like ourselves and our pets.
Levulis: And to those next steps, are you able to detail what they might be in terms of research now that this study is out there?
Rich: Yeah, so we'll go back and we'll probe to find the particular, presumably it's a protein in the blood, and figure out what it's acting on in the bacteria in order to define those precise mechanisms. So it'll all be very molecular work that's designed to understand the mechanisms, the interactions between the mechanisms in the bacterium and the deer.
Levulis: No this study looked at white-tailed deer, what about other species of deer?
Rich: Yeah, so white-tailed deer are the principal species that we have here in the Northeast and upper Midwest, where Lyme disease is endemic. So it's the most important deer species. There are other things like sika deer and mule deer and other species that in other parts of the country support ticks that transmit things like Lyme disease. And interestingly enough, some of those deer had already been studied and known to have this effect on the Lyme pathogen, but it hadn't been studied in white-tailed deer, the most important species. And one of the reasons for that is, well, first of all, it's somewhat difficult to work with white-tailed deer because they're a game species. And so it's difficult to get blood. But more importantly, it's difficult to get blood from deer that haven't likely been fed on by ticks that have Lyme disease. There is probably is no place in New England or the upper Midwestern United States, where such deer would exist. So that's where it was very valuable to have these collaborators at the University of Auburn, that had a captive deer population that had not been exposed to ticks or Lyme in the past.
Levulis: Looking beyond this study, I wonder if there are any predictions for how active, I don't know if that's the right choice of words, of a Lyme season, this spring, summer fall might be based on the conditions this winter and so far this spring in the Northeast?
Rich: You know, Jim, we get that question almost every year, like ‘is it going to be a big year or a small year?’ And while some of my colleagues like to prognosticate about that, we know that it's really hard to predict whether there's going to be an exceedingly high or exceedingly low season and what we just encourage people to know is that ticks are going to start being active as soon as it warms up above 40 degrees. They're going to remain active throughout the spring and into early July, when then there's somewhat of a senescence as it goes into larval season and then there's another peak season in the fall. And so whether it's five ticks that are going to bite you in your backyard or three and a half, it's probably very difficult to predict because things are so localized. So we just want people to be aware more about the seasonality rather than the absolute numbers.
