Hey, it's Flora Lichtenen, and you're listening to Science Friday.

Today in the podcast, Lyme disease, and the progress and pitfalls around preventing, treating, and even understanding it.

I've been working on this for 30 years, and I can say that part of my career is filled with abject failure.

It is pure tick in some parts of the country, and data suggests it may be the worst

tick season in years. Fordham's tick index even rates concrete jungle New York City as high

risk at the moment. Of course, the big concern is diseases tick-carry, including Lyme disease. Without quick treatment, Lyme disease can be debilitating, spreading to the joints, muscles, and nervous system, prompting arthritis symptoms with the side of brain fog. So here is the question on my mind, why is there no vaccine

for Lyme disease? There's a Lyme disease vaccine for dogs. We've had it for years. Why not one for

people? Here to take a bite out of this question is Dr. Lyndon, who, an immunologist and Lyme disease

specialist at Tufts Medical School in Boston, Massachusetts. Lyndon who, an immunologist and Lyme disease specialist at Tufts Medical School

in Boston, Massachusetts. Linden, welcome to Science Friday. Oh, thanks so much. Glad to be here.

Why is this year so bad for ticks? You know, I'd say that's really hard to say. There are probably

lots of different factors involved, but things like how cold the winter was,

how much snow cover there was.

So typically more snow has an insulating effect, so it helps keep the ticks alive a little bit better.

Very cold weather will kill the ticks.

Once we get out of winter, one of the big things that affects it is how much moisture there is. Ticks survive heat pretty well, but they do not survive lack of moisture. So when we have a dry spell, it often will wipe out tick populations. So even seasons that start out very robust with lots of ticks, if we hit a dry spell, the tick populations will crash. Let's talk a little bit about Lyme disease. It's a bacteria. What does it do in the body?

So it's actually a really wimpy bacteria in a lot of ways. It's very dependent on its environment

to survive, and it can't survive outside a tick or mammalian host. So typically what happens is an infected

tick will bite you or bite an animal. You know, most of how this is maintained in the wild is

through small rodents and pass between ticks and rodents. And we're kind of incidental to all

of this. We get accidentally infected. But when it passes to a human, it usually

starts at the site of the tick bite. The bacteria exit the tick and enter into the skin, and it starts

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