This mystery meat allergy starts with a tick bite

CHAPEL HILL, N.C. -- 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.

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.