Alpha-gal syndrome: Lone star tick (and other ticks) & allergy to mammal meat: hives, indigestion, anaphylaxis

This may some people with unexplained sensitivity & hive reactions, especially if you've been in areas of the US where the lone star tick exists (or along beaches in Sydney Australia, where another tick can cause a similar reaction ... article says there are ticks around the world that can cause similar things.) This could also explain (in some cases) symptoms consistent with MCAS (mast cell activation syndrome).
It's worth reading the entire article, but it's long, so I've pasted in the key parts below.

McGraw is allergic to the meat of mammals and everything else that comes from them: dairy products, wool and fibre, gelatine from their hooves, char from their bones. This syndrome affects thousands of people in the US and an uncertain but likely larger number worldwide, and after a decade of research, scientists have begun to understand what causes it. It is created by the bite of a tick, picked up on a hike or brushed against in a garden, or hitchhiking on the fur of a pet that was roaming outside.

The illness, which generally goes by the name “alpha-gal allergy” after the component of meat that triggers i

Ticks detect scent with organs embedded in their first pair of legs, and what they’re sniffing for is carbon dioxide, the exhaled breath of an animal full of warm, oxygenated blood. When lone star ticks catch wind of it, they take off. “The Lyme disease tick is a slow tick,” says Dr William Nicholson, a microbiologist at the CDC. “Amblyomma will run to you.”

There has been so little research into alpha-gal allergy that scientists can’t agree on exactly what stage of the bite starts victims’ sensitisation. One aspect of its epidemiology is becoming clear, though: the allergy isn’t only caused by the lone star tick..]


[An Australian tick can cause this, too.]
In Australia, Van Nunen (who is now a clinical associate professor at the University of Sydney School of Medicine) couldn’t understand how her patients’ tick bites solved the mystery of their meat allergy.
In 2007, Van Nunen wrote up a description of 25 meat-allergic patients whose reactions she had confirmed with a skin-prick test. All but two had had severe skin reactions to a tick bite; more than half had suffered severe anaphylaxis. The crucial detail in Van Nunen’s research was that her cases were caused by bites from Ixodes holocyclus, called the paralysis tick. Alpha-gal allergy was not just an odd occurrence in one part of the US. It had occurred in the opposite hemisphere, making it literally a global problem.

And so it has proved. Wherever ticks bite people – everywhere other than the Arctic and Antarctic – alpha-gal allergy has been recorded.

Food allergies are overwhelmingly caused by proteins, tend to surface in childhood and usually trigger symptoms quickly after a food is consumed. Alpha-gal is a sugar; alpha-gal patients tolerate meat for years before their reactions begin; and alpha-gal reactions take hours to occur. Plus, the range of reactions is far beyond what’s normal: not only skin reactions in mild cases and anaphylaxis in the most serious, but piercing stomach pain, abdominal cramps and diarrhoea as well.

But alpha-gal reactions are definitely an allergy, given patients’ results on the same skin and IgE tests that immunologists use to determine allergies to other foods.
The name of the sugar was galactose-alpha-1,3-galactose, known for short as alpha-gal.

While Lyme clusters in the north-east and the northern midwest US, diseases carried by Amblyomma stretch from the coast of Maine to the tip of Florida, the Atlantic to the middle of Texas, and the southern shores of the Great Lakes all the way to the Mexican border. And that range appears to be expanding.
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Senior Member
U.S., Earth
Alpha-gal syndrome

Wikipedia said:
Alpha-gal allergy — or mammalian meat allergy (MMA)[1] — is a type of meat allergy characterized by a delayed onset of symptoms (3–8 hours) after ingesting mammalian meat and resulting from past exposure to tick bites. It was first reported in 2002. Symptoms of the allergy include rash, hives, nausea or vomiting, difficulty breathing, drop in blood pressure, dizziness or faintness and severe stomach pain.[2]

Alpha-gal allergy is a reaction to galactose-alpha-1,3-galactose ("alpha-gal"), whereby the body is overloaded with immunoglobulin E (IgE) antibodies on contact with the carbohydrate.[3] Anti-gal is a human natural antibody that interacts specifically with the mammalian carbohydrate structure gal alpha 1-3Gal beta 1-4GlcNAc-R, termed, the alpha-galactosyl epitope.[4] The alpha-gal molecule is found in all mammals except catarrhines (apes and Old World monkeys),[4] the taxonomic branch that includes humans.

Bites from certain ticks, such as the lone star tick (Amblyomma americanum) in the US, and the paralysis tick (Ixodes holocyclus) in Australia, which can transfer this carbohydrate to a victim, have been implicated in the development of this delayed allergic response to consumption of mammalian meat products.[5] Individuals with alpha-gal allergy do not need to become strict vegetarians, because poultry, fish, and in rare cases for some people, lean meat such as venison does not trigger a reaction.[6]
I got tested for it a few years ago because i became alkergic to milk of multiple species and intolerent of many meats. It was negative and I was disappointed..