Red Meat Allergies Triggered By Tick Spit Are Increasingly Common: CDC

ACROSS AMERICA — Nearly half a million Americans may be living with a meat allergy triggered by tick spit, according to a pair of studies released Thursday by the Centers for Disease Control and Prevention.

The first study estimated as many as 110,000 Americans developed an allergy to red meat between 2010-2022 because of alpha-gal syndrome, or AGS. But, the CD said the true number of Americans who have developed the allergy may be closer to 450,000.

That would make it the 10th most common food allergy in the country, Dr. Scott Commins, a University of North Carolina researcher who co-authored both papers, told The Associated Press.

Health officials said they are not aware of any confirmed deaths, but people with the allergy have described it as bewildering and terrifying.

“I never connected it with any food because it was hours after eating,” one patient, Bernadine Heller-Greenman, told the AP.

Scientists discovered in 2011 that the alpha-gal sugar could be spread through tick bites, tying it to the lone star tick, which is common in the eastern and southern United States.

The increases are due in part to the expanding range of lone star ticks, but also because doctors are testing more for the antibody.

But many aren’t. In a survey of 1,500 health care workers last year, 78 percent said they had little or no knowledge of the syndrome, and only 5 percent said they felt very confident they could diagnose it.

Dr. Ann Carpenter, an epidemiologist and lead author of one of the papers, called alpha-gel syndrome “an important emerging health problem, with potentially severe health impacts that can last a lifetime for some patients.”

“It’s critical for clinicians to be aware of AGS, so they can properly evaluate, diagnose, and manage their patients and also educate them on tick-bite prevention to protect patients from developing this allergic condition,” Carpenter said in a news release announcing the studies.

Health officials said they aren’t aware of any confirmed deaths related to the allergy.

The AGS reaction occurs when an infected person eats beef, pork, venison or other meat from mammals — or ingests milk, gelatin or other mammal products. It’s not caused by a germ but by a sugar, alpha-gal, that is in meat from mammals — and in tick spit. When the sugar enters the body through the skin, it triggers an immune response and can lead to a severe allergic reaction.

People who have been infected usually notice symptoms within two and six hours after eating food or ingesting other products containing alpha-gal, including gelatin-coated medications.

Symptoms include hives or an itchy rash; nausea or vomiting; heartburn or indigestion; diarrhea; cough; shortness of breath or difficulty breathing; drop in blood pressure; swelling of the lips, throat, tongue, or eyelids; dizziness or faintness; or severe stomach pain.

Some people only have stomach symtoms, and the American Gastroenterological Association says people with unexplained diarrhea, nausea and abdominal pain should be tested for the syndrome.

Doctors counsel people with the allergy to change their diet, carry epinephrine and avoid tick bites.

The allergy can fade away in some people — Commins has seen that happen in about 15% to 20% of his patients. But a key is avoiding being re-bitten.

“The tick bites are central to this. They perpetuate the allergy,” he said.

One of his patients is Heller-Greenman, a 78-year-old New York art historian who spends summers on Martha's Vineyard. She has grown accustomed to getting bitten by ticks on the island and said she has had Lyme disease four times.

About five years ago, she started experiencing terrible, itchy hives on her back, torso and thighs in the middle of the night. Her doctors concluded it was an allergic reaction, but couldn't pinpoint the trigger.

She was never a big meat eater, but one day in January 2020 she had a hamburger and then a big, fatty steak the following evening. Six hours after dinner, she woke up nauseated, then suffered terrible spells of vomiting, diarrhea and dizziness. She passed out three times.

She was diagnosed with alpha-gal syndrome shortly after that, and was told to avoid ticks and to stop eating red meat and dairy products. There have been no allergic reactions since.

“I have one grandchild that watches me like a hawk," she said, making sure she reads packaged food labels and avoids foods that could trigger a reaction.

“I feel very lucky, really, that this has worked out for me," she said. “Not all doctors are knowledgeable about this.”

CDC officials urged anyone who thinks they may be infected to see a doctor or allergist and also emphasized the importance of preventing tick bites.

The Associated Press contributed reporting.