Yes, Some Tick Bites Can Cause a Meat Allergy—and a New Study Shows It’s More Common Than We Thought

Long pants? Check. Bug spray? Check. If you're a hiker or live in a wooded area, these steps before leaving the house may be second nature. But why do we take these precautionary measures to avoid things like ticks?

This may be news to you, but certain tick bites can cause a rare red meat allergy, also known as alpha-gal syndrome. While only about 110,000 cases have been recorded in the U.S. between 2010 and 2022, scientists with the Centers for Disease Control and Prevention (CDC) just discovered that number might actually be a lot higher—thanks to two other species of ticks not previously associated with the illness.

Last week, the CDC and local health officials published two studies in the journal Emerging Infectious Diseases, noting an increase in alpha-gal syndrome from the western black-legged tick (Ixodes pacificus) and deer tick (Ixodes caupularis). Normally, bites from both ticks are associated with Lyme disease (a bacterial infection that can cause a rash, flu-like symptoms, and joint pain). But recently, they've shown that they can trigger a rare red meat allergy, too.¹

Alpha-gal syndrome in most cases develops as a result of a lone star tick bite—a common species located on the east coast of the U.S. But what is alpha-gal—and how do you know if you've developed the syndrome?

What is alpha-gal?

Alpha-gal is a sugar found in almost all mammals except for humans. This means it can be found in animal products like red meat, pork, dairy, gelatin, and certain medications. Normally, humans can tolerate and digest alpha-gal sugars without any problems, but for some reason, a bite from certain ticks can trigger an overreaction in your immune system toward alpha-gal. In other words, your body starts to see meat—and other alpha-gal-containing products—as a threat, per the Emerging Infectious Diseases study.

When you're bitten, alpha-gal sugar transfers from the tick's saliva and into your bloodstream. Your body then develops alpha-gal antibodies (i.e., proteins made by your immune system), which trigger an allergic reaction every time you eat something containing alpha-gal.² Unlike other food allergies, this syndrome sensitizes you to a sugar, not a protein.

You'll usually find out if you have alpha-gal syndrome through bloodwork, to see if any antibodies are present in your blood. Your healthcare provider will also ask a series of questions about your history of tick bites to learn more information before confirming a diagnosis.³

Symptoms look similar to other food allergies

Symptoms of alpha-gal syndrome (or red meat allergy) are similar to other allergic reactions from food and may include:

• Hives or rashes
• Nausea and vomiting
• Abdominal pain
• Shortness of breath
• Diarrhea
• Drops in blood pressure
• Swelling of the lips, tongue, or eyelids
• Dizziness or faintness
• Heartburn or indigestion
• Anaphylaxis, in rare cases (i.e., a life-threatening allergic reaction that requires immediate medical care)

Usually, symptoms will appear three to six hours after eating red meat or other alpha-gal-containing products, depending on the severity of your allergy. Keep in mind: This is different from typical food allergies that can cause almost immediate reactions.

Can alpha-gal syndrome be treated?

Unfortunately, there is no cure for alpha-gal syndrome; however, typical food allergy treatments do work to manage the condition. Yale Medicine says this includes medications like epinephrine (EpiPen), antihistamines, and oral corticosteroids. Beyond that, the only way to prevent symptoms is to avoid meats and other animal food and products that contain alpha-gal, such as dairy, pork, and certain medications. But as always, it's important to talk to your healthcare provider if you're ever unsure of what to avoid.

Studies have also found that alpha-gal antibodies can decline over time, meaning you may be able to eat meat again in the future. But if you get more tick bites, your sensitization and reactions will get worse.⁴ This is why it's important to avoid tick bites in the first place.

How to prevent tick bites

If you're a big hiker or camper—or live near the woods—you can't completely avoid the possibility of encountering a tick. That said, here are a few strategies from the CDC to reduce the likelihood of being bitten:

• Be on the lookout for them in grassy and wooded areas
• Spray your clothing and gear with products like permethrin
• Walk in the center of trails when hiking and avoid wooded areas with high grass or leaves
• Use an EPA-approved insect repellent, such as DEET, picaridin, or oil of lemon eucalyptus

The bottom line

Now that we know more ticks can cause alpha-gal syndrome than we previously thought, it's important to keep a lookout even if you haven't thought about ticks much before. Sure, getting a meat allergy from a tick bite sounds concerning. But it's important to keep in mind that if you're diligent about protecting yourself when you go outside, you can significantly reduce your chances of contracting the condition.