Massachusetts recently joined more than a dozen other states in mandating doctors and blood labs to report cases of an unusual tick-borne syndrome known as alpha-gal.
The very dangerous and sometimes fatal condition makes those who contract it allergic to red meat and occasionally to mammal products like dairy. Reactions can be mild, but in many cases, they send patients into anaphylactic shock. In 2024, a pilot became the first known person to die from alpha-gal after eating a hamburger at a barbecue.
The illness is caused primarily by the lone star tick, and for more than a decade was most common in Arkansas, Kentucky, and Virginia, where doctors have long been reporting cases.
But now, as the disease spreads, up to 450,000 Americans may be living with the syndrome, according to a Stony Brook University report. Many are unaware they have it until that first allergic reaction.
Tony Haigh of Bella Vista, Ark., is living with alpha-gal. He considers himself lucky because he reacts to mammal products only by breaking out in hives.
“I had hives just covering my body for about three weeks, and it led me to, you know, try to get some testing done and figure this out,” Haigh said, “and luckily was identified rather quickly in my case.”
Allergist and immunologist Dr. Tina Merritt diagnosed Haigh at the Allergy and Asthma Clinic of Northwest Arkansas in Bentonville. Merritt is known for her research on alpha-gal and helped develop the test to detect it.
Reactions range from hives to nausea and vomiting to anaphylaxis at worst, Merritt said.
“The hard part with alpha-gal is it’s usually delayed. And so, some people may not associate their reaction with the hamburger they had at dinner,” Merritt said. “And it’s usually at 2 in the morning; they’ll wake up with dizziness. That means their blood pressure is low … And when the blood pressure drops, they usually describe dizziness, but it happens very quickly, and so they may not have much time to get attention.”
9 questions with Tony Haigh and Tina Merritt
Was your diagnosis scary? How did you clear up the hives?
Tony Haigh: “Certainly scary. I carry an EpiPen now. I’ve luckily never needed it, but I make sure I never travel without one and always have one in my truck if needed.
“Stopping red meat and all mammal products is, of course, the first thing that you do. But the first year that I had it was actually quite tough on me. And so, the remedy is just a lot of antihistamines. And now I eat a lot of chicken and eggs and vegetables.”
How conscious are you of avoiding meat?
Haigh: “It is very real. If I go to a restaurant, it’s absolutely a concern that there may be cross-contamination. If I have family or friends who are cooking a meal for me, they may think that, you know, they’ve modified to help me, which I’m very grateful for. But oftentimes that turkey or chicken sausage that they’re substituting has a pork or beef casing.”
Dr. Merritt, at the University of Virginia, you knew Dr. Thomas Platts-Mills. He was also studying allergies. He’d been contacted by somebody who had a cancer drug, and people were having adverse reactions. They couldn’t figure it out. He tested and found that some of the alpha-gal antibodies were in that cancer drug.
Tina Merritt: “It was made in an animal cell line, and they had attached a carbohydrate that we found out later was alpha-gal. Then Dr. Platts-Mills figured out it was in the distribution of the ticks. So, the lone star tick distribution, so it was mainly in the Mid-South at the time. And so that was my area because I moved to Arkansas, and then a patient passed away from that cancer drug from their first infusion. And so, I called them, and I said, ‘Hey, we got to get this test going again.’ And so that’s how the test got developed. But he figured out it was tick bites. He figured out it was beef and pork-related. And it’s just kind of grown in information from there. But it was also described in Australia about 30 years before we did.”
How does the tick get that molecule and then bite a human and deposit it? Does it ever go away?
Merritt: “There’s a group in Mississippi that measured tick saliva, and they found the lone star tick and the blacklegged tick, which is more common on the eastern coast, they both contain alpha-gal in their saliva.
“We think it might go into remission if you don’t get bitten again. The hard part is if you get bitten again, your immune system develops a good memory, and you may not be able to go into remission.”
Haigh: “A fear of mine is getting bit by another tick that’s infected and having my symptoms get worse.”
Cases on Martha’s Vineyard grew from two in 2020 to more than 500 in 2024, according to the Martha Vineyard Hospital. Some people there, even tourists, are taking up strict and sometimes permanent vegan diets so they won’t get the symptoms.
Merritt: “The hard part is there’s a lot of mammal ingredients and several things that we use just in daily use. So, it could be problems with products. So, if your skin breaks out from your shampoo, is it the mammal ingredients? It could be. If you’re taking a medication, if it has a gelatin capsule, or even sometimes pills can have a binder. There’s one called magnesium stearate. There’s pre-gelatinized starch. So, I myself have alpha-gal. I was dizzy for six months before I realized the pill I was taking had magnesium stearate and pre-gelatinized starch.
“I’ve had it probably since third grade, but we didn’t know what it was back then. Stomach aches was my main symptom back then.
“In third grade, I was bitten by seed ticks at Girl Scout camp in Louisiana. And then I was calling my parents on hamburger day with stomach aches. I thought I was being punished on Good Friday for eating a hot dog.”
What’s your advice to people scared of contracting alpha-gal?
Merritt: “There are some plant-based insect repellents. There’s also DEET and permethrin. There’s even different clothing lines that have tick repellent in the clothes. Also, you can treat your own property if you feel like there’s a tick potential in your property. If you have pets, you can treat your pets. So, the main thing is just trying to reduce your tick bite exposure.”
Are there people out there who are undiagnosed?
Merritt: “Absolutely. I think a lot of people go undiagnosed, and they go to the gastroenterologist. They go to the dermatologist, and you know, they may not know this is what was the cause of their symptoms. I’ve had patients that were having symptoms for five years before they found out that they had alpha-gal.”
Do all lone star ticks have alpha-gal?
Merritt: “We’re not sure. It’s very difficult to measure tick saliva, but the group in Mississippi did measure tick saliva, and the lone star ticks and the blacklegged tick contained alpha-gal in their saliva. And it’s present in the little, tiny seed ticks as well as the adult ticks.”
Has this changed how you live your life?
Haigh: “I try to not let fear impact my life too much. I still live an outdoor life. I’m not going to stop walking my dogs in the woods. I’m not going to stop mountain biking, but I’m more aware. One thing that I just really am glad about is that this is getting more attention. And people are becoming more aware of it.
“Probably one of the most impactful things that could happen is having a food label, something like a gluten-free or a vegan food label would be hugely impactful for people that suffer with this.
“Again, you go to a restaurant and you don’t know about cross-contamination and you know people are using beef tallow and fry later, so you may think you’re doing the right thing and eat a French fry and have a reaction.”
This interview was edited for clarity.
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Karyn Miller-Medzon produced and edited this interview for broadcast with Todd Mundt. Allison Hagan adapted it for the web.
This article was originally published on WBUR.org.
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