Alpha-gal is a relatively unknown syndrome that has medical professionals scratching their heads the more they learn about it.
The public also wants to know more, with many taking to Google to find out about the syndrome. Search data shows 3.7k monthly searches globally for “Alpha-gal symptoms” and a further 1.1k questioning “What is Alpha-gal syndrome?”.
As such, the experts at Allergy Insider have put together three helpful facts about Alpha-gal to aid with understanding.
What is Alpha-gal syndrome?
Also known as red meat allergy and tick-bite allergy, the syndrome is an allergic reaction to Alpha-gal, which is a sugar molecule found in mammal meat such as beef, pork, venison, and more 1-2. But this reaction actually begins with a bite from a tick (or possibly harvest mites)2-3.
The tick (or harvest mites) feasts on a mammal such as a deer, and in doing so, it ingests Alpha-gal. If it bites a human, it can transmit Alpha-gal into the person’s bloodstream 2-3. In some people, this triggers an immune response when the person later eats mammalian meat, which can cause mild to severe and even life-threatening symptoms2.
According to the Centers of Disease Control and Prevention (CDC), the US is thought to have up to 450,000 people affected by Alpha-gal syndrome, which is already starting to rise as warmer temperatures create a more favourable environment for ticks.
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A cancer-related drug trial led to the discovery of Alpha-gal Syndrome4
Alpha-gal Syndrome was discovered via drug trials for cetuximab, which is an antibody treatment aimed at colorectal cancer and cancer of the head and neck that contains Alpha-gal. A number of patients enrolled in the clinical trials developed anaphylaxis or hives after the first dose of cetuximab. This mysterious reaction led to further investigation and later to the identification of the syndrome in the mid-2000s.
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The list of Alpha-gal Syndrome symptoms seems to be getting longer, and some symptoms can mimic those of Irritable Bowel Syndrome (IBS)5
Symptoms of Alpha-gal syndrome can run the gamut from an itchy rash and hives to diarrhoea and anaphylaxis6. In fact, anaphylaxis occurs in up to 60% of people with the syndrome7. However, according to survey results presented at the American Academy of Allergy, Asthma & Immunology Annual Meeting, some Alpha-gal Syndrome patients have a wide range of seemingly new symptoms, such as those involving the cardiovascular, emotional, nervous, and motor systems. In particular, patients in the survey reported a wide range of mental health issues, such as anxiety, depression, fatigue, poor memory, irritability, sleep disturbances, etc8.
Additionally, Alpha-gal symptoms may closely resemble those of IBS. According to a 2021 study in the Journal of Gastroenterology, some people with Alpha-gal Syndrome only have gastrointestinal symptoms, such as abdominal pain, nausea, and diarrhoea. Many of these symptoms overlap with IBS, and 56% of patients in this study met the criteria for diarrhoea-predominant IBS5.
Based on this study and the fact that some healthcare providers aren’t familiar with Alpha-gal Syndrome, it stands to reason that symptoms of Alpha-gal Syndrome can be confused with those of IBS5.
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Across the globe, bites from several types of ticks (and potentially harvest mites) can lead to Alpha-gal Syndrome3,4,6.
Initially, this syndrome was linked to the Lone Star Tick, which is found mostly in the southeastern United States2. However, Alpha-gal Syndrome has now been reported on all continents except Antarctica, and at least eight tick species are confirmed or suspected culprits associated with the condition9.
Additionally, at least some tick species have extended beyond their typical home turf. That is, as hosts such as deer move into different territories, so do ticks that hitch a ride on them. So thanks to different patterns of land use, climate change, and increasing deer populations, ticks like the Lone Star Tick have spread. For example, the Lone Star Tick was previously rare in Michigan, but it’s now the third most common tick in the state4. Plus, a 2022 article in the Toronto Star revealed that the tick is expanding into Canada due to rising temperatures10.
Some of the symptoms of Alpha-gal include hives, sneezing, stomach pain and anaphylaxis, among many others. And, as there is no explicit Alpha-gal syndrome treatment, it’s vital to receive a proper diagnosis to know what products and foods to avoid.
However, you need to get the right test straight out of the gate, and a skin-prick test (SPT) probably isn’t the way to go. In fact, SPTs with extracts of pork or beef have been unreliable in detecting alpha-Gal.
Rather, ask your healthcare provider for a blood test. You want an Alpha-gal specific IgE component test. Additionally, your provider may want to test for beef, pork, lamb, alpha-Gal, total IgE, and tryptase to help develop a clear diagnosis.
To continue reading about Alpha-gal syndrome, head to Allergy Insider’s blog for all 10 facts and extra information.