The Most Dangerous Tick Lurking In the U.S.

tick insect warning sign in forest
© Gabor Tinz/

Written by Nina Phillips

Published: May 10, 2024

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Ticks are a huge problem. If not caught quickly enough, they can cause Lyme disease, Rocky Mountain spotted fever, and lifelong health problems for you and your pets. However, one species of tick is even more dangerous than the other 90-something species in the United States. Keep reading to find out what the most dangerous tick in the U.S. is, and why it’s such a problem.

The Most Dangerous Tick in the United States

The dot on the back of this tick gives away the fact that it’s a female lone-star tick.

©Judy Gallagher / CC BY 2.0 – Original / License

The most dangerous tick in the United States is without a doubt the lone star tick (Amblyomma americanum).

This tick species is dangerous because not only does it carry Lyme disease, as many ticks do, but it can cause people to get allergic reactions to red meat and their by-products. This is known as alpha-gal syndrome. It gets its name from the sugar molecule in many mammals. Those bitten by a lone star tick and get this syndrome develop allergic reactions to pork, beef, lamb, venison, rabbits, dairy, and gelatin.

Every person’s reaction to this syndrome is a little different. Some have mild hives and dizziness, while others can get anaphylaxis, a drop in blood pressure, and swelling of the eyelids and tongue.

Where This Tick Lives

Welcome to Texas State Sign

Texas is just one of many states where you’ll find lone star ticks.

©miroslav_1/iStock via Getty Images

Lone star ticks are found in central Texas and Oklahoma, all the way to the east, and as far north as Maine. However, they are most common in Southern and Eastern parts of the United States.

What it Looks Like

Lone Star Tick (Amblyomma americanum) on a white background.

Lone star ticks are easy to identify from other species.


Lone star ticks are relatively easy to identify, especially the females. All of these ticks, at any age, have brown and red bodies that are oval in shape. When they overeat, they often turn grey.

The male version of this tick will have small white horseshoe-looking markings across their back. Females, however, are where the species gets their common name. They have one white dot on the back, which looks like a lone star. This dot is often in the center of their back and is very obvious.

When Lone Star Ticks Are Most Active

Lone star ticks are most active when the weather is warm. Depending on where in the United States you are, this is usually in the summer, and in parts of spring and fall. The southeasternmost part of the United States will usually experience these ticks from early spring to late fall.

How to Avoid Ticks

Detail of man hiking

Ticks can be anywhere while you’re hiking, so it’s good to be prepared.

©Gajus/iStock via Getty Images

These ticks are often a problem for you and your pets. Any time you’re outdoors, especially when going on walks or a hike, you want to be prepared. This means wearing clothing that covers your skin, like boots, long socks, and pants. Additionally, permethrin is a spray you can apply to your clothes and that lasts several washes. Or, you can buy clothes that already have permethrin in them. DEET bug sprays are also effective against ticks.

Stay Safe on Trails

When out on your walk, whenever possible, try to avoid places with high grass, leaf litter, and wooded areas. Try walking in the center of trails so things can’t brush up against you.

Inspect and Heat Clothes

Taking measures when you come home is also an important step, especially with your pets. You always want to take time to check your clothes for ticks before heading inside. To be extra safe, take off those clothes immediately and tumble-dry them for at least 10 minutes.

Examine Geat and Oets

Take time to examine all of your gear, like backpacks, headbands, and any other fabric ticks can attach to. If you bring your dog with you, inspect their skin, including areas between their toepads and the soft spots.

Check Yourself

When you get inside, check yourself as well. Even if there appeared to be no ticks on your clothes, there might have been one on your person.

You always want to check:

  • Your hair
  • In and behind the ears
  • The belly button
  • Your waist
  • Between your thighs
  • Back of your knees
  • Under your arms
  • Private places

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About the Author

Nina is a writer at A-Z Animals, FIDIS Travel, and Giant Freakin Robot. Her focus is on wildlife, national parks, and the environment. She has been writing about animals for over three years. Nina holds a Bachelor's in Conservation Biology, which she uses when talking about animals and their natural habitats. In her free time, Nina also enjoys working on writing her novels and short stories. As a resident of Colorado, Nina enjoys getting out in nature, traveling, and watching snow hit the mountains from her enclosed porch.

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