According to recent estimates, nearly half a million Americans are already living with this unpleasant disease.
Photo: María LENZ
An unusual epidemic has gripped the United States; The number of people allergic to meat is increasing in the country. According to recent estimates, nearly half a million Americans are already living with this unpleasant disease. Furthermore, intolerance to meat and dairy products occurs after the bite of a certain species of tick with the romantic name of Amblyomma americanum or the “lone star” tick, so called probably because of the white spot on the back of the tick. tick is somewhat reminiscent of the Texas state flag.
How did such an unusual type of allergy arise when people who have been eating beef at barbecues for years suddenly can’t stand the meat anymore? Nikolai Kryuchkov, candidate of medical sciences, immunologist and general director of a contract research company, explained to Komsomolskaya Pravda why this meat intolerance syndrome can be life-threatening in some cases and whether forced rejection of red meat and milk threatens the Russians.
In recent years, between 15,000 and 17,000 new cases of allergies to red meat and dairy products have been reported in the United States, but the problem itself came to the attention of doctors only recently, in the early 2000s.
– At first we simply began to notice similar cases, people who developed intolerance to dairy and meat products (red meat, beef, pork, lamb). Then they began to study this phenomenon and after a couple of years it was possible to compare it with a certain event – a tick bite. Finally, scientists have discovered the main component of the saliva of some ticks, which is responsible for the development of alpha-Gal allergy, says Nikolai Kryuchkov. – In America, one species of tick, Amblyomma americanum, is dangerous in this regard, but there are other ticks from the ixodid family, whose bites can also cause a similar allergy.
WHAT IS THIS ALFA-GAL AND HOW DOES A MEAT ALLERGY DEVELOP?
Alpha-Gal is contained in the glycoproteins of tick saliva along with a large amount of biologically active substances, including those that cause serious infections, in which ticks are so rich.
Alpha-Gal is a disaccharide that is not produced in the human body, so its molecule is perceived as foreign by the immune system.
– Normally, the immune system synthesizes IgM antibodies, which help control the development of infections. But when a tick bite occurs, its saliva contains a whole “cocktail” of biologically active substances that, upon entering the human body, shift the immune response in at least two ways towards a specific Th2 immune response, says Nikolai Kryuchkov.
What does this mean in practice? This type of immune response is also called “allergic” because it is accompanied by multiple allergic reactions. The immune system begins to synthesize IgE class antibodies that, with a certain cellular interaction, begin to release histamine into the environment, causing an allergic reaction. In addition, mature immune cells also switch to the synthesis of IgE antibodies.
– Alpha-Gal is found not only in tick saliva, but also in red meat, milk and animal products such as gelatin, for example. Therefore, as soon as the immune response changes after a tick bite and a person eats some red meat containing alpha-gal, the immune reaction is activated. Furthermore, this reaction is delayed and its deployment takes 2 to 6 hours, says our expert.
WHAT ARE THE SYMPTOMS OF A MEAT ALLERGY?
Common manifestations of meat allergies are:
– symptoms similar to those of “indigestion”: pain and heaviness in the abdomen, nausea, vomiting;
– rash: very itchy in different parts of the body. It appears suddenly, lasts a while and disappears.
In this case, the person does not even think that he has some kind of allergy to alpha-Gal, since its manifestations are very vague and not acute. Rather, in this case, people do not go to the doctor and begin to choose diets from foods that do not cause discomfort, they think that they are developing gastritis or heartburn.
Where can meat allergies be common in Russia?
It is necessary to be attentive to these symptoms, first of all, in Siberia and beyond the Urals: these are regions of our country rich in various ticks. However, such a nuisance as a tick bite from the genus Ixodidae can also occur in the European part of Russia, especially during the period of tick activity. If about 4,000 cases of tick-borne borreliosis or Lyme disease are recorded annually in our country, it is clear that, in general, the number of bites recorded is higher. Plus, there are even more unrecorded bites that people simply don’t pay attention to.
“It should be noted that not all tick bites provoke the development of allergy to alpha-Gal,” says Nikolai Kryuchkov. – Several factors must come together: this is the danger of the tick itself and how rich its “salivary cocktail” is in glycoproteins with alpha-Gal. In addition, the state of the immune system of the person who received the bite and certain genetic factors also influence.
When can a meat allergy be life-threatening?
There are examples from the early 2000s where people with similar allergies were given a drug (monoclonal antibodies to treat cancer) and a small number of people developed severe anaphylactic reactions. At that time the connection with tick bites was not yet suspected, but through more detailed observations it was possible to link this severe allergic reaction to the alpha-Gal drug and the tick bite.
HOW TO PROTECT YOURSELF?
– If you suspect that you have an intolerance to meat and dairy products (see symptoms above), you can have a test, for example, a quantitative test that measures the level of IgE antibodies against alpha-Gal (IgE anti-alpha-Gal).
– Pass a skin test for allergens, including meat allergen.
– If alpha-Gal syndrome is confirmed, its negative manifestations can be prevented by following a restrictive diet and excluding meat (beef, lamb, pork) and dairy products from the diet.
– It is important to protect yourself from ticks. Alpha-Gal syndrome is another reason not to communicate with these small creatures that carry several dangerous infections at once, such as tick-borne borreliosis and tick-borne encephalitis, for example.
Why is it important to know your allergic reactions?
As life progresses, the degree of an allergic reaction can change, increase or, on the contrary, decrease. The variety of allergens (in this case, meat products) can also change over time, meaning that controlling your sensitivity can prevent accidental anaphylactic shock.
