Tick Bites Causing Meat Allergy
We recently published an article in the Herald about tick bites that cause bacterial infections. We related that there are different species of ticks and each type carries specific bacteria that can cause specific diseases through a bite. The most common tick in the Lake Area is the Lone Star tick, sometimes called the deer tick.
Researchers have now learned that the bite of a Lone Star tick can result in the victim of the bite developing an allergy to meat. Most mammals, except humans, harbor a sugar compound known as alpha-gal. The Lone Star tick, and possibly others, also carry alpha-gal and when they bite a human they can transmit this sugar to the bite victim. When introduced to the human blood system, it can trigger an immune response to red meat and other mammalian products. Basically, what happens is that when alpha-gal enters our body, our immune system makes large amounts of antibodies to the sugar causing the person to be hypersensitive to the alpha-gal sugar that is contained in all meat products. This causes the person to have a meat allergy, similar to the more common food allergies some people have to shellfish and nuts.
When a person previously exposed to alpha-gel ingest meat products, an allergic reaction occurs which can be mild or very serious. Now, we don’t only have to worry about tick bites causing bacterial infections, but a tiny tick bite can trigger an allergic reaction to steak, burgers, and pork.
Interestingly, the first allergic reaction may not occur for up to 3 months after the bite. Also, the symptoms of a reaction typically don’t occur for 3-6 hours after ingesting meat. Therefore, meat ingested at dinner time would result in symptoms occurring in the middle of the night. This is in contrast to typical food allergies that occur in a matter of 15-30 minutes after exposure. It is becoming apparent that a large percentage of people who have a meat allergy actually have Alpha-gal Syndrome (AGS).
Typical symptoms of AGS may include any combination of the following: hives or itchy, scaly skin (eczema); wheezing and difficulty breathing; runny nose with sneezing and headache; and abdominal pain with diarrhea and vomiting. The most serious reaction is anaphylaxis, whereby bronchial tubes in the lungs constrict causing severe breathing difficulty and blood pressure drops resulting in life threatening shock. This situation requires immediate administration of an epinephrine injection and transport to the nearest hospital emergency room.
There are case reports of people with AGS, in addition to being allergic to consuming meat products, are also allergic to anything that comes from mammals. This includes some dairy products, wool fibers and even gelatin (made from mammal’s hooves).
AGS can be diagnosed by a blood test to measure the presence of antibodies to the alpha-gal sugar. As with any food allergy, treatment involves avoiding foods that cause the allergic reaction. Some food allergies can be helped with a desensitization process by an allergist, but currently this is not available for AGS. It is important to check labels on commercial food products to be sure that they don’t contain meat-based ingredients that might be added to a product for flavoring. In some people, a reaction can occur if food is consumed that has been cooked in a pan that was previously used to cook a meat product.
Most people with AGS will improve or the sensitivity will completely resolve with time, but clinical studies have shown the time frame for improvement is typically 18-36 months, assuming no further tick bites.
Because of the potential for anaphylaxis, anyone with AGS should carry a self -injecting epinephrine pen at all times.
Alpha-gal syndrome is just one more reason that people should take preventive steps to avoid tick bites, including using insect repellant and wearing long pants and sleeves when outside in woody and grassy areas. Also, it is important to do a full body check after spending time outdoors.
Dr. Tippett is the founder of Comprehensive Quality Healthcare Providers, a concierge internal medicine practice located at 1210 Commerce Dr. Suite 106, Greensboro, Ga. 30642. He can be reached at 706-510-3659. Visit his webpage at www.drtippett.com