Warm weather patterns mean more human contact with ticks

Host Amber Smith: Upstate Medical University in Syracuse New York invites you to be The Informed Patient with the podcast that features experts from Central New York's only academic medical center. I'm your host, Amber Smith.

Dr. Saravanan Thangamani's tick surveillance program has analyzed more than 27,000 ticks since it opened in 2019, so he's got a good idea about what's happening among ticks in Central New York. He's a professor of microbiology and immunology at Upstate, and he's here to give us a tick outlook. Welcome back to "The Informed Patient," Dr. Thangamani.

Saravanan Thangamani, PhD: Thanks for having me.

Host Amber Smith: We had such a warm fall this year. Does that make for a more hospitable environment for the ticks?

Saravanan Thangamani, PhD: Yes. There is a direct correlation between warm weather and increasing human tick encounters. Because when the weather is warm, we spend more time outside doing outdoor activities, trekking and walking in the woods. And ticks are always there. When it is warm they try to stay at the tip of the grass, waiting for some human to walk by, and they latch onto them. They go into hibernation only when the temperature goes below, I would say, 35 degrees Fahrenheit. They start to kind of slow down their metabolism. They try to kind of find nice, cozy places right under the leaf litter or debris so that they prepare for the harsh winter. And that's how they survive during the harsh winter.

I must tell here that even in winter, people encounter ticks. So, through our program, we have received ticks even in January and February. You'd be surprised. Because people, they do snowshoe walking. They trek. They do hunting sometimes in the winter. And they put themselves at risk of tick exposure, as well.

Host Amber Smith: But aren't people more bundled up so that their skin is covered, if they're out in the wintertime? How would ticks get to them?

They start to crawl on the winter clothing first. And then they find a way to go around the head, or when you have a wool or cotton hat, these ticks can attach to them and they can try to squeeze themselves into the threads. And then they wait. When you go home, and you try to take your hat and put it on your basket, and then it comes out and start to find somebody else in the home. We don't know how we are carrying, actually. There are many ways how the ticks, they don't have to attach right away. They can actually wait for you even inside the home. They can wait for you and then just wait for the right person to come by.... How long can a tick last without being fed? If a tick got in your house, and it was just sitting on a counter, how long could it live before it had to eat something?

Saravanan Thangamani, PhD: I would say at least couple of years.

Host Amber Smith: A couple of years?

Saravanan Thangamani, PhD: Yes. So, as long as there is good humidity there. In the winter we heat our homes, right? So it's a little bit dry environment, and that is not good for the ticks. But in summer, we air-condition our homes. We give enough moisture and humidity inside the home, so they can live. But ticks are very clever. They will always find a corner where it's not too dry. Obviously they will try to go away from the dry to a moisture area, like in the bathrooms. They will find ways to survive there all the time. Doesn't matter if it's winter or summer because, you know, we use water all the time, which means that is good enough for the ticks. Ticks can be, ticks can go for a couple of years without taking a blood meal. They are very hardy.

So ticks don't die during the winter. They are very clever to find warm places for them to hide and wait until the spring warm weather comes up. They start to come out and try to find a human to feed on.

Host Amber Smith: So all of these ticks from the fall, the ones that are young, or babies, they're wintering over, and they're going to be waiting for us in the spring?

Saravanan Thangamani, PhD: Yes. So if they take a blood meal in the fall, they molt, they become the next stage, and they wait for us in the spring.

Host Amber Smith: Great.

Saravanan Thangamani, PhD: So, the more ticks we have now means that there will be more ticks in the spring as well. So we saw 20% more ticks in the fall, which means that I'm now projecting that in the spring we will see almost at least 20% increase in the number of human-encounter ticks in the lab. And again, we are only focused on what we receive in the lab. So the caveat is that, can we actually project this to the entire state in a even distribution way? I cannot tell that because unfortunately, whoever is encountering the tick and whoever is aware of our program, they actually send the tick to us. So, although we try to disseminate our tick testing information throughout the state of New York. So there is a little bit of biases there, so we are trying to address that. But that's a general trend is there, that we will get definitely more takes this 2023 spring.

Host Amber Smith: Well, Dr. Thangamani, thank you so much for giving us this update. I appreciate your time.

Saravanan Thangamani, PhD: Thank you very much for having me.

Host Amber Smith: My guest has been Dr. Saravanan Thangamani. He's a professor of microbiology and immunology at Upstate. And you can learn more about his research on tick-borne diseases at nyticks.org -- that's N Y T I C K S DOT O R G. "The Informed Patient" is a podcast covering health, science and medicine, brought to you by Upstate Medical University in Syracuse, New York, and produced by Jim Howe. Find our archive of previous episodes at upstate.edu/informed. This is your host, Amber Smith, thanking you for listening.