Chattanooga has a richly deserved reputation as one of the country’s best spots for spending time outdoors. Our lush landscape beckons Chattanoogans to go outside and play, often in the woods. Unfortunately, this area is also home to several species of ticks. One of these ticks, the Lone Star tick, found mostly in the Southeast, has contributed to a new problem. When these ticks bite people, a chain reaction occurs that can lead to an unusual meat allergy. Some of the proteins from the tick’s saliva can trigger the development of allergic antibodies against galactose alpha 1,3 galactose (Gal Alpha Gal).
Dr. Todd Levin, a double board certified Allergy-Immunologist at Chattanooga Allergy Clinic, says that these allergic antibodies are found in mammalian meats such as beef, pork, lamb, goat, buffalo and venison. The reaction is not like typical allergic reactions to foods such as peanut, where the reaction occurs immediately after exposure. In Mammalian Meat Allergy Syndrome (otherwise known as Gal Alpha Gal allergy), the reactions are delayed, occurring anywhere from 3 to 6 hours after ingestion. “Since attending a conference by the people that discovered this new allergy 2 years ago, Chattanooga Allergy Clinic has seen nearly twenty patients with Gal Alpha Gal allergy,” says Levin. “Our experience with this type of allergy has allowed us to make this often difficult diagnosis, by asking the right questions about diet and tick exposure.” Mammalian Meat Allergy can develop within a few weeks of a tick bite, but the diagnosis may take longer to sort out. In fact, there may be other potential causes yet to be discovered. To speed up the diagnostic process, the physicians at Chattanooga Allergy Clinic take a detailed history of the allergic reaction, focusing on the timeline of when each food was ingested. Once Gal Alpha Gal allergy is suspected, Levin says that cutting edge lab tests developed by researchers at the University of Virginia can confirm the diagnosis.
These patients can experience typical symptoms of food allergies including hives, itching, and swelling. Some patients may even have anaphylaxis, a severe allergic reaction that includes nausea, vomiting, diarrhea, shortness of breath, drops in blood pressure, and rarely, passing out.
Gal Alpha Gal can be found in nearly all routinely eaten mammalian meats, but it is not present in fish or poultry. People and primates do not have Gal Alpha Gal. It can be found in small amounts in cow’s milk and gelatin, which is made from animal products. Gelatin is found in some pill capsules, marshmallows, candies, and of course, Jello. “Even though there have been some reports of people reacting to milk or whey containing protein powders,” Levin says, “most patients that have Gal Alpha Gal can tolerate dairy products.” Interestingly, many patients will initially only react to one type of meat, most commonly beef, but later on, may become sensitive to other red meat.
As far as treatment goes, Dr. Levin says that the best advice is avoidance of red meat since there is currently no cure. Patients should always carry an epinephrine auto-injector such as EpiPen in case of accidental exposure. Research looking at the course of this syndrome is ongoing, but it looks like some patients can “outgrow” this allergy if they avoid the trigger foods strictly and don’t get any more tick bites.
Chattanooga Allergy Clinic is now accepting new patients. Please call (423)899-0431 for an appointment.