More and more people are being diagnosed with Alpha-gal syndrome, which is an allergic reaction to mammalian products. Alpha-gal is a sugar molecule found in the saliva of ticks.
Dr. Charity Owusu-Asare, an allergist at CoxHealth, said when a tick bites a person, it injects alpha-gal into the blood, and the body makes antibodies to it.
"And so once these antibodies are made, we call it sensitization or we, I mean, for a simple term could be like the body gets primed with it. Now some individuals who have made these antibodies, right? When they eat anything that contains alpha-gal, such as mammalian meats, we have beef, we have pork, we have lamb, we have venison," she said. "Once this is ingested, these also contain alpha-gal. So now the body thinks this is a problem, right? For some individuals, and then it triggers an allergic reaction."
The lone-star tick has been cited as one of the tick species that transmits alpha gal, but other ticks carry it in their saliva as well.
Alpha-gal allergies have a range of symptoms. Mercy Springfield Allergist Dr. Sylvia Huebner said some people have gastrointestinal symptoms, such as nausea, vomiting, diarrhea and pain. Some develop skin reactions like hives, rashes and itching. And some experience more serious symptoms like anaphylaxis with throat and tongue swelling. She said a person who experiences anaphylaxis should seek medical treatment immediately. Antihistamines can help with the milder symptoms.
Huebner said there’s a lot about alpha-gal syndrome that’s still unknown.
"We don't understand why some patients have minimal symptoms with ingestion and some people have very severe symptoms with ingestion. And when you run the lab, work on them, when you obtain Alpha-gal IGE panel, the alpha gal number per se is not indicative of symptom severity, which is kind of interesting," she said. "So, you know, we have patients who have anaphylaxis with really low levels and patients who have higher levels that actually tolerate the food, interestingly, so we don't quite understand that."
Typically, allergies cause a pretty immediate reaction. But, Owusu-Asare said, with alpha-gal, symptoms can appear anywhere from two to eight hours after consuming food like beef, pork and dairy. So, a person who consumes mammal meat or dairy with dinner might wake up in the middle of the night with symptoms if they have an alpha-gal allergy.
And the time between a tick bite and when symptoms develop varies, too.
"Some have had symptoms within a couple of weeks. Others have had symptoms several months later," she said, "so it varies with different people."
She said not everyone who is bitten by a tick and produces antibodies, which sensitizes them to alpha-gal, will develop an allergy and therefore symptoms.
For those that do have it, avoiding mammalian products is the best course of treatment.
Both Huebner and Owusu-Asare said alpha-gal allergies don’t typically last more than a few years. Symptoms typically improve until they are gone. And Owusu-Asare said people who once couldn’t eat red meat without developing symptoms have been able to gradually add it back to their diet.
There’s still debate over whether more people are developing alpha gal syndrome or whether there's more awareness of it, and the medical community is better at diagnosing it. Huebner said she’s not sure there’s an answer to that. But she tends to lean toward the fact that more testing is being done now so more people are being diagnosed with alpha-gal allergies.
"Way back when, before alpha-gal was recognized and, you know, there was really not that long ago in reality, you know, patients would be diagnosed with chronic hives or IBS, irritable bowel syndrome, and those kind of diagnoses. And then, you know, you would figure out, hey, this patient has alpha-gal," she said. "But we finally actually found a cause behind those symptoms."
The Centers for Disease Control and Prevention advises that the best way to prevent developing alpha-gal syndrome is to use EPA-registered insect repellants that contain active ingredients like DEET and picaridin. Wear clothing and gear treated with permethrin, and shower and check for ticks after going indoors.
