Ticks and Alpha-gal Syndrome
If I already have alpha-gal syndrome, why do I need to avoid ticks?
If you have alpha-gal syndrome, it is important to avoid additional tick bites. If you are bitten again, your alpha-gal IgE levels can increase. If you aren’t bitten your alpha-gal IgE will likely decline over time and with luck, so will your reactivity. (12,13)
Which Tick Species Can Cause Alpha-gal Syndrome?
Ticks associated with, or in some cases suspected of being associated with, the onset of alpha-gal syndrome include:
- In the U.S., the Lone Star Tick (Amblyomma americanum) (1)
- In Europe, the Castor Bean Tick (Ixodes ricinus)(2), Rhipicephalus bursa (3), and Hyalomma marginatum (3)
- In Australia, the Australian Paralysis Tick (Ixodes holocyclus) (4) and (Ixodes endopalpiger australiensis) (5)
- In Central America, Ixodes cajennense(6)
- In Japan and Korea, possibly Ixodes nipponensis? (7)
- Also in Japan, Haemaphysalis longicornis (8) and Amblyomma testudinarium (9)
- In Brazil, possibly Amblyomma sculptum? (7)
- In the Ivory Coast, possibly Amblyomma variegatum? (7)
- In South Africa, the vector of sensitization has not yet been identified.
What We Don’t Know About Ticks and AGS
- We don’t know which other species of ticks can cause alpha-gal syndrome, although it’s likely that others do.
- We don’t know if Black-legged Ticks (Ixodes scapularis) can cause alpha-gal syndrome. They may, as they have alpha-gal in their saliva and are closely related to other species that do. (10)
- We don’t know if chiggers can cause AGS. There is speculation that they might. (11)
- We don’t know if other ectoparasites or endoparasites can trigger AGS, although it’s thought that they may. ()
How Do Ticks Cause AGS?
- Ticks eject saliva into the bite sites they create in the skin.
- The saliva triggers an immune response that leads to alpha-gal syndrome.
- The mechanism by which this occurs is still being studied, but it’s believed that AGS is triggered by alpha-gal in ticks’ saliva, possibly in conjunction with adjuvants.
How Long Does a Tick Have to Feed to Trigger AGS?
- It can take many hours for ticks to transmit some diseases, but they can trigger AGS as soon as they bite you and eject their saliva into your skin.
- For this reason, it is best to avoid tick bites in the first place, not just remove ticks promptly after they bite you, although you should do that, too.
I was at a party and felt something crawling on my leg inside my jeans. I pulled down my jeans and looked for the critter. My gf got poed and interrupted my search. Got home a few hours later and she found the Lonestar tick attached on my hip. Looking for a new gf.
Do All People Who Are Bitten by Ticks That Can Trigger AGS Get It?
- No, most people who are bitten by ticks that can trigger AGS do not develop AGS.
What Other Illnesses Can I Get from Ticks?
If you are bitten by a tick, you might not just develop AGS. You might also acquire a tick-borne disease.
- Ticks transmit many diseases.
- Different tick species transmit different diseases.
- If you get AGS after a tick bite, don’t assume that all the symptoms you experience afterwards are caused by it.
- Talk to your doctor about ruling out tick-borne diseases and other illnesses which could be contributing to your symptoms.
- Learn more about North American tick-borne diseases and the species that transmit them from the CDC.
I remember finding what I thought was a dog tick on my belly and thinking, “Oh good! It is not a deer tick! I don’t have to worry about Lyme with this one!” HA! Five weeks later, I woke in a full body rash. Four additional weeks later, I was diagnosed with Alpha Gal. Life has been on an unchartered course ever since. However, I remain hopeful and positive!
1. Commins, S. P., et al. (2011). “The relevance of tick bites to the production of IgE antibodies to the mammalian oligosaccharide galactose-α-1,3-galactose.” Journal of Allergy and Clinical Immunology 127(5): 1286-1293.e1286.
2. Hamsten, C., et al. (2013). “Identification of galactose-alpha-1,3-galactose in the gastrointestinal tract of the tick Ixodes ricinus; possible relationship with red meat allergy.” Allergy 68(4): 549-552.
3.Mateos-Hernandez, L., et al. (2017). “Tick-host conflict: immunoglobulin E antibodies to tick proteins in patients with anaphylaxis to tick bite.” Oncotarget 8(13): 20630-20644.
4. Van Nunen, S. (2007). “THE ASSOCIATION BETWEEN IXODES HOLOCYCLUS TICK BITE REACTIONS AND RED MEAT ALLERGY” ASCIA 2007 ALLERGIC DISEASE POSTERS.” Internal Medicine Journal 37(s5): A128-A135.
5. Kwak, M., et al. (2018). “A novel Australian tick Ixodes (Endopalpiger) australiensis inducing mammalian meat allergy after tick bite.” Asia Pac Allergy 8(3): e31.
6. Wickner, P. G. and S. P. Commins (2014). “The First 4 Central American Cases Of Delayed Meat Allergy With Galactose-Alpha-1,3-Galactose Positivity Clustered Among Field Biologists In Panama.” Journal of Allergy and Clinical Immunology 133(2, Suppl. S): AB212.
7. van Nunen, S. A. (2018). “Tick-induced allergies: mammalian meat allergy and tick anaphylaxis.” Med J Aust 208(7): 316-321.
8.Chinuki, Y., et al. (2016). “Haemaphysalis longicornis tick bites are a possible cause of red meat allergy in Japan.” Allergy 71(3): 421-425.
9. Hashizume, H., et al. (2018). “Repeated Amblyomma testudinarium tick bites are associated with increased galactose-α-1,3-galactose carbohydrate IgE antibody levels: a retrospective cohort study in a single institution.” J Am Acad Dermatol 78(6): 1135-1141.e1133.
10. Crispell, G., et al. (2019). “Discovery of Alpha-Gal-Containing Antigens in North American Tick Species Believed to Induce Red Meat Allergy.” Front Immunol 10: 1056.
11. Stoltz, L. P., et al. (2019). “Could chiggers be contributing to the prevalence of galactose-alpha-1,3-galactose sensitization and mammalian meat allergy?” J Allergy Clin Immunol Pract 7(2): 664-666.
12. Commins SP. Diagnosis & management of Alpha-gal Syndrome: Lessons from 2,500 patients. Expert Review of Clinical Immunology. 2020 Jun 25. Forthcoming.
13. Kim MS, Straesser MD, Keshavarz B, Workman L, McGowan EC, Platts-Mills TA, Wilson JM. IgE to galactose-α-1, 3-galactose wanes over time in patients who avoid tick bites. The Journal of Allergy and Clinical Immunology: In Practice. 2020 Jan 1;8(1):364-7.