Giving Ticks Drymouth | Headline Science

This is a western black-legged tick. And this is how ticks drink your blood. T hey work their barbed mouthparts under your
skin, and then they drink up. But there’s a part of the story you can’t
see. Just like your spit is essential to eat your
food, a tick’s spit is essential to eat their food. See this weird-looking thing? This is the salivary gland from a Lone Star
Tick. Tick spit does three things:
It dilates blood vessels, which brings more blood to the area. It stops your blood from clotting, which ensures
a steady blood flow. It suppresses your immune response, which
makes the tick harder to detect and remove. Oh, and tick spit can also carry the bacteria
that causes Lyme disease, which is injected into your blood as the tick feeds. If you’re trying to get rid of ticks in
a cornfield, you can use commercially available insecticides, which are mostly neurotoxic. But that’s not a good idea in, say, your
backyard. Which is why Daniel Swale and Zhilin Li from
Louisiana State University are working on a way to kill ticks by going after their spit. Swale and Li fed lone star ticks cow blood
laced with different molecules to see if they had any effect on how much spit a tick could
make and how much blood it could eat. Okay, this is a tick’s salivary gland under
a microscope magnified approximately 30 times. By the way, we’re playing this video at
about 14 times the normal speed. As you can see, the gland is secreting spit. That’s that little globule forming. Now here’s a gland from a different tick. This one was treated with a potassium channel
inhibitor developed by Swale and his colleagues. And as you can see, it’s not working like
it’s supposed to. There’s no spit. Next, Swale and Li tried their new drug in
live ticks. It reduced the amount of blood ticks drank
by 15-fold and it also had other effects. Here’s a tick that was fed regular cow’s
blood. She looks just fine. This tick was fed cow’s blood laced with
the potassium channel inhibitor. Life is not good for this little tick right
now. Their new drug also killed ticks within 12
hours, which is good, because it takes at least 12 hours for a tick to transmit most
pathogens, like Lyme disease. Swale and Li are presenting these findings
at the American Chemical Society Fall National Meeting in San Diego.