Alpha-gal syndrome creates nasty reaction to red meat

Host Amber Smith: Upstate Medical University in Syracuse, New York. Invites you to be The Informed Patient, with the podcast that features experts from Central New York's only academic medical center. I'm your host, Amber Smith.

Maybe you've heard about an allergy to red meat. It's an immune reaction to the carbohydrate molecule called alpha-gal, and researchers believe it's triggered by a tick bite.

Here to discuss this emerging and unique food allergy is Jamie Romeiser. She's an assistant professor of public health and preventive medicine at Upstate.

Welcome back to "The Informed Patient," Dr. Romeiser.

Jamie Romeiser, PhD: Thank you so much for having me, Amber.

Host Amber Smith: This is called alpha-gal syndrome. How did it get its name?

Jamie Romeiser, PhD: Well, alpha-gal refers to a carbohydrate. That carbohydrate is called "galactose-alpha-1, 3-galactose," and that's found on the tissue of mammals, with the exception of humans and primates.

So alpha-gal syndrome is also known as that red meat allergy, which you alluded to, because it is an allergy to that carbohydrate, and it's really unique, as a food allergy. As you said, the way that it is triggered or induced in people is likely from a tick bite, which injects that alpha-gal carbohydrate into the person's bloodstream.

So in some people, their body then is going to develop antibodies to alpha-gal. So when somebody with those elevated antibodies consumes something that contains alpha-gal, like red meat, for example, it might induce this allergic reaction.

Host Amber Smith: Do we know how many people are affected by alpha-gal allergies?

Jamie Romeiser, PhD: Not exactly. So in the U.S., we don't have a national surveillance system for alpha-gal. So we are somewhat limited in what we know in terms of the new cases that occur every year in the total cases. But that being said, there are some estimates that have used laboratory data and extrapolated that data, which does put this estimate between 100,000 and 450,000 people who have been affected.

Host Amber Smith: So significant, especially if you're one of the ones affected by it, it sounds like.

Jamie Romeiser, PhD: Yes.

Host Amber Smith: Now, I know you're not an MD, a medical doctor, but can you tell us what symptoms people report?

Jamie Romeiser, PhD: Sure. These symptoms really range. They can be more mild, something from itchy palms, to something that can present as full-body hives, nausea or vomiting, stomach pain, GI (gastrointestinal, or digestive) symptoms, dizziness.

And then it can also get a little bit more severe, to things like anaphylaxis (a life-threatening reaction).

So something that's really important to point out with these symptoms is that if you do have symptoms, they're going to be delayed. So, for example, if somebody with this allergy eats a burger or a steak, they're not going to have symptoms right away. It's going to appear two to eight hours later.

Host Amber Smith: So not like if you were having like food poisoning issues or something, this wouldn't confuse you.

Jamie Romeiser, PhD: It potentially could confuse you, but it's different from other allergies, in that with other food allergies, these reactions tend to happen right away, whereas this is more delayed.

Host Amber Smith: So I want to ask you how this is diagnosed, but before we get into that, the sequence of events is: A person gets bitten by a tick, and then how much longer until they have potentially reactions to meat?

Jamie Romeiser, PhD: That delay can happen about two weeks. So if somebody is bit by a tick, it takes a little while for antibodies to develop in a person, so you might not, be potentially allergic right away. But then, potentially, two weeks later, if you were to eat a burger or steak, and then you eventually have something happen about two to eight hours after that, that's when your symptoms can arise.

Host Amber Smith: So how does a doctor go about diagnosing this?

Jamie Romeiser, PhD: Usually it's a combination between actually identifying that those symptoms are a delayed reaction to red meat. And so once you have that patient history established, then a confirmation can actually come in through a blood test, and that blood test can measure the amount of alpha-gal antibodies in a person's bloodstream.

Host Amber Smith: Is there a treatment available?

Jamie Romeiser, PhD: If you've had an exposure, and you're having symptoms, mild reactions could be treated by antihistamines. More severe reactions could be treated with an injection of epinephrine and perhaps additional treatments provided from an emergency department, but in terms of a real treatment or a cure, no.

So treatment in this case is avoidance, and it's really avoidance of two different things. It's avoidance of another tick bite, and it's also avoidance of things that might cause that reaction.

And what you end up having to avoid is really individualistic. Everybody has different sensitivities. In most cases, that's red meat, but in some cases it might extend to things like avoiding dairy and avoiding gelatin or other mammalian-derived products that might cause a reaction.

Host Amber Smith: Does the allergy get better on its own, or do people potentially have to give up meat forever?

Jamie Romeiser, PhD: It depends on the person, so it doesn't always last forever in everybody. A little disclosure, I've actually had alpha-gal myself, and with me it lasted about two and a half years. So for some people, the allergy can get better over time, and if it does, what happens is your blood levels of that alpha-gal antibody can drop if you avoid recurrent tick bites and if you avoid those exposures to red meat and other products, so in some people it does go away, but in others it might take a really long time.

Host Amber Smith: Which tick is implicated in this?

Jamie Romeiser, PhD: So in the U.S., the type tick that is mostly associated with inducing this allergy is a lone star tick. Adult females have that little white star on their back, but the adult males don't. The primary habitat for these ticks are the Southeast U.S., but warmer weather has been leading to an expansion of habitat, which does mean that these ticks are moving northward. So in regards to New York state, they're very common in Suffolk County, New York, which is in Long Island. but there is evidence that they're beginning to expand their habitat up to Central New York.

Host Amber Smith: Did you just get sick eating meat?

Jamie Romeiser, PhD: So the story is, I used to live in Suffolk County, which is the eastern, county in Long Island, and these lone star ticks are really prevalent there. I knew of a couple people who had the allergy, and so I was really aware of it. And a couple of ticks, I'm going to blame the dog, hitched a ride on my dog, inside.

And I ended up waking up one night with, a tick bite, and I was like, "Oh no! OK," -- which is not uncommon in Long Island. It's almost a way of life.

And so it was about two weeks later when I had a really nice, beautiful, steak dinner and woke up in the middle of the night with really, this, it's hard to explain the feeling -- almost like this existential dread the world was going to end, and I just felt awful.

And it turned out I was covered in head-to-toe hives, and it was not a good scene, and I sort of knew exactly what it was, just from putting the pieces together.

Host Amber Smith: Is it just beef, or would that have happened with lamb or pork or venison?

Jamie Romeiser, PhD: It would've happened with any of them, but from what we know, the level of your reaction, it does depend on the person, but it also is linked to the fat of the meat. So if you have something that is pork, which is more lean, or venison, which is more lean, you might not have as severe reaction as if you do with like bacon or steak, because that seemed to have a higher concentration of alpha-gal in those particular products.

And it also depends on how much you eat, too.

Host Amber Smith: How did you have the courage to try another steak in the future?

Jamie Romeiser, PhD: Oh, it was a long time (laughs), and even now, if you're talking about sort of forced vegetarianism (laughs), it took me a while, and I still don't eat a lot of red meat products.

It did take two and a half years. That first time that my antibody levels came down enough. You know, we tested them, every six months basically. I went to my allergist, and she said, "You know, at some point they're low enough. You can, you can do it."

And I was like, "OK." I tried a little bit, actually just a little, just to see (laughs).

Host Amber Smith: This is Upstate's "The Informed Patient" podcast. I'm your host, Amber Smith.

I'm talking with Dr. Jamie Romeiser from Upstate's department of public health and preventive medicine about alpha-gal syndrome.

You and two colleagues have a paper about this published in the Journal of Medical Internet Research.

What can you tell us about it?

Jamie Romeiser, PhD: Let me set up the premise a little bit for our study. A couple years ago, there was a survey of people who had alpha-gal, and those participants reported that it took them, on average, seven years to actually get a confirmed diagnosis. That's a really long time.

And a couple of reasons are: One, it's, again, really unconventional as a food allergy. Those delays in symptoms after exposure. And that the symptoms are really different in everybody, it makes it hard to make that connection sometimes. And sometimes people don't know that they've been bitten by a tick, so it's another piece of the puzzle that might be missing.

But when we put together puzzles, we know that it's a lot easier if we actually know the picture on the box of what we're supposed to be putting together, right? So a large reason for this delay in diagnosis is that the allergy is not well known. It's not known in the general public, it's not well known in the medical community.

And a case in point with that, another recent survey of health care providers found that 42% were not aware of alpha-gal syndrome. And of the people who were, only about a third were comfortable diagnosing it and managing it.

So with this knowledge gap, this leads people who have the allergy to actually search for information on their own and try to navigate the syndrome on their own.

And what's something that most of us do when we want to learn information about something? We Google it, right? We type into the search engine engine, and we Google things.

So what our study did was, we conducted an "infodemiology" study, which focuses on understanding the different information-seeking patterns, specifically for the topic of alpha-gal.

Host Amber Smith: So you looked at what people were looking for, what kind of information they were looking for and what they were able to find.

Jamie Romeiser, PhD: Exactly. So what we wanted to look at was, how has this volume of searches changed over time? We also wanted to know different geographic areas where people were searching for this. Where was it really common?

And we wanted to understand those different concerns and topics that people were looking for in relation to alpha-gal. And so that last part, understanding really what people were looking for, their overarching concerns, we were thinking that this might be able to serve as a template of conversation topics between health care providers and patients.

Host Amber Smith: Did you identify any themes or subcategories?

Jamie Romeiser, PhD: We did. We identified quite a few, came up with some major theme topics of what people were searching for. And to be honest, a lot of them overlap with the questions that we're covering on the interview, so that's really great. These major themes include diet, various symptoms, general education about the allergy, getting a diagnosis, information on ticks and medications.

We did a little bit deeper dive of this data, too, and what seemed to be pretty clear was that there's a big interest in concealed sources of exposures to alpha-gal. So things like food additives, things like additives to medications, like gelatin and gel caps, which contain a small amount of alpha-gal.

Animal products in general are pretty ubiquitous in food and medications and other products, and so it seems like there's really a need for improved food and product labeling because from what we can tell with this data and different experiences with people, they're really struggling with identifying sources of exposure and identifying things that might contain alpha-gal.

Host Amber Smith: Did you find geographic interest in Central New York?

Jamie Romeiser, PhD: We couldn't drill down, to specific areas within each state. And so that's a limitation of this data. We could only really see this at the state level. So geographically what we were able to see was that your highest interest levels for looking for alpha-gal were really more focused in the South and Southeastern states of the U.S. We also looked at this over time, and that stayed pretty consistent over the past eight years.

Host Amber Smith: Do you think that the increase in searches for alpha-gal indicates an increase in the incidence of disease or just an increase in the interest or the fear?

Because this sounds kind of scary, really.

Jamie Romeiser, PhD: It does sound a little bit scary, that's true. And it's complicated, and it's challenging. And I think, to answer your question, I think they go hand in hand. We did find a rapid increase in volume, specifically from 2015 through 2022. People are searching for this a lot more.

If you look at that rate of increase for searching for alpha-gal, that rate of increase is much higher than things like food allergies, which stay consistent pretty much over time. They've stayed pretty consistent from 2015 through 2022.

So what we think this might be is the combination of things.

Yes, the diagnosis is increasing. We know that this is happening from lab data, but we also think that it is a sign of increased awareness of the allergy, especially in the past few years. There's been a push for public education on the topic, so hopefully that can help with more timely diagnoses.

Host Amber Smith: Did anything surprise you or jump out in your study?

Jamie Romeiser, PhD: I think sort of it did. So I was mostly surprised at some of the geographic pattern portion of this study. In some ways it makes perfect sense what we saw. So the search volumes were highest in the areas that have historically higher numbers of alpha-gal cases, but what we did was we compared these geographic patterns of searching for alpha-gal with geographic patterns of searching for lone star ticks. So we basically took two maps and we overlaid those maps to see how they were correlated. And they were very highly correlated, of course, with alpha-gal searches and lone star tick searches.

But one thing that we did notice was that the geographic area, for information searching for lone star ticks was actually more expansive. And specifically, this was more expanded into the Northeastern areas and Midwestern states, and so those searching patterns actually do match the lone star tick habitat expansions.

So we know that there are also cases of alpha-gal in the Northeast and in the Midwest. And so I think that this can really be taken sort of as a signal that it's time to expand education efforts about alpha-gal to the general public and to health care providers in these states where lone star ticks do have habitat.

Host Amber Smith: Before we wrap up, I want to ask you to kind of summarize what you think regular people need to know about alpha-gal, especially as someone like yourself, who had this. Do you have any repercussions, any lingering symptoms?

Jamie Romeiser, PhD: I don't have any lingering symptoms. So it has really subsided in me, which I consider myself fortunate to be one of those people.

I think one of the things that helped me out the most was awareness of the allergy. The reason why I received such a timely diagnosis is that I knew about the allergy. I knew that it was triggered by a tick bite. I knew that there was a delay in symptoms. I knew what to look for, and so I think that that awareness is really paramount in being prepared for this allergy.

I think the other thing, of course, is prevention of tick bites. So you can treat your clothing, you can treat your outdoor gear, you can perform tick checks after being outdoors and check your pet, which is really important. And if you don't live in an area where lone star ticks are well established, you could end up visiting one of those areas.

So it's something to really be aware of. Prevention and awareness is key, that delayed reaction, as well. So, hopefully, we can get the word out. information campaigns are spreading, which is good. And if you are looking for more information about the allergy, you can check out evidence-based information sources, like the CDC (Centers for Disease Control and Prevention).

Host Amber Smith: Once a person has had alpha-gal, do they have immunity or do you have to be careful about future lone star tick bites?

Jamie Romeiser, PhD: Funny you should ask that, and I'm a good person to ask that. I actually got alpha-gal twice. The first time it lasted about two and a half years, and then the allergy subsided enough.

And then unfortunate circumstances happened that I was bit again, and it induced the allergy again. So you can get it multiple times. And again, I was fortunate enough that that's also subsided, so it's not something that you can have immunity to.

Host Amber Smith: Well, that's good to know, and I appreciate you making time to tell us about this, Dr. Romeiser.

Jamie Romeiser, PhD: Thank you so much for having me.

Host Amber Smith: My guest has been public health researcher Dr. Jamie Romeiser. "The Informed Patient" is a podcast covering health, science and medicine, brought to you by Upstate Medical University in Syracuse, New York, and produced by Jim Howe.

Find our archive of previous episodes at upstate.edu/informed.

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