Mystery Meat Allergy Starts With A Tick Bite


CHAPEL HILL, N.C. (Ivanhoe Newswire) — Most of us enjoy a good, juicy burger from time to time. But imagine if eating red meat triggered a severe allergic reaction! At one time, it was very rare reaction and limited to a few hundred people in the southern United States. But now, as ticks begin to migrate north, experts say it’s a health problem that is on the rise!

Like many Americans, Darrow enjoys a good steak.

“Three hours after that delicious beef tenderloin I started itching,” Darrow said.

It got so bad she ended up in the ER!

“It felt like fire ants from head to toe,” said Darrow.

Turns out Darrow was suffering from an unusual food allergy, and she’s not alone.

“We are confident of 5,000 cases. They had no idea that two hours after eating a hamburger that in another two hours they’d be covered in hives and have severe itching,” said Scott Commins, MD, UNC Division of Allergy, Immunology & Rheumatology.

Dr. Commins and his team at the University of North Carolina wanted to know what was causing an allergic reaction in people like Darrow who never had a food allergy. Dr. Commins says the culprit appears to be the lone star tick, prevalent in the southeast. They reached out to patients who reported reactions.

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Dr. Commins said, “sure enough, over 90 percent of them reported recent tick bites.”

It’s called the alpha-gal allergy. Named after a sugar found in the blood of certain animals such as cows and pigs.

“A tick takes a blood meal off a lower mammal like a deer or dog and then bites a human,” explained Dr. Commins.

The tick has alpha-gal in its saliva, which can trigger an allergic reaction when that person eats red meat. But there is some good news!

“I am so careful now when I go outside no matter where I am,” Darrow told Ivanhoe.

So she doesn’t become a meal for a hungry tick again.

Darrow will be re-tested in about eight months to see if her alpha-gal levels are still high. Dr. Commins says allergic reactions vary in patients and some may need to carry an epi-pen. He adds the lone star tick has expanded up the east coast and as far north as Minnesota.

Contributors to this news report include: Janna Ross, Field Producer; Roque Correa, Videographer; Cyndy McGrath, Supervising Producer; Hayley Hudson, Assistant Producer; Roque Correa, Editor.

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REPORT:       MB #4516

 BACKGROUND: Alpha-gal syndrome is a recently identified type of food allergy to red meat. In the United States, the condition most often begins when a Lone Star tick bite transmits a sugar molecule called alpha-gal into the body. In some people, this triggers an immune system reaction that later produces mild to severe allergic reactions when they eat red meat. The Lone Star tick is found predominantly in the southeastern United States, and most cases of alpha-gal syndrome occur in this region. The condition appears to be spreading farther north and west, however, as deer carry the Lone Star tick to new parts of the United States. Alpha-gal syndrome also has been diagnosed in Europe, Australia, and Asia, where other types of ticks carry alpha-gal molecules.


SYMPTOMS: Signs and symptoms of an alpha-gal allergic reaction are often delayed compared with other food allergies. Most reactions to common food allergens — peanuts or shellfish, for example — happen within minutes of exposure. In alpha-gal syndrome, signs and symptoms typically don’t appear for three to six hours after eating red meat. Signs and symptoms of alpha-gal syndrome may include hives, itching, or itchy, scaly skin, swelling of the lips, face, tongue and throat, or other body parts, wheezing or shortness of breath, a runny nose, abdominal pain, diarrhea, nausea or vomiting, sneezing, headaches, or anaphylaxis: a severe, potentially deadly allergic reaction that restricts breathing.


RESEARCH: Researchers are also trying to figure out what it is about ticks that causes this reaction. They’re looking at deer blood, tick saliva, and bacteria from ticks as possible causes, and there’s now research around the world, with cases of meat allergies resulting from tick bites coming from Australia and Europe, although as a result of different kinds of ticks. Once this is better understood, there’s hope of someday having a treatment that could desensitize people through allergy shots.  In the meantime, researchers say it’s important that medical professionals other than allergists know about this condition. They say doctors need to understand that abdominal pain is a key marker of this allergy and that symptoms are delayed.



Bradd Pavur, PR UNC School of Medicine


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Doctor Q and A

Read the entire Doctor Q&A for Scott Commins, MD, PhD, Associate Professor of Medicine & Pediatrics

Read the entire Q&A