Lone star tick causes alpha-gal meat sensitivity in regional population

American College of Allergy, Asthma, and ImmunologyNov 9 2012

Meat lovers living in the central and southern regions of the country might be opting for a vegetarian lifestyle if meat comes with an unwanted side of a life-threatening allergic reaction. According to a study presented at the Annual Scientific Meeting of the American College of Allergy, Asthma and Immunology (ACAAI), the lone star tick inhabiting these regions is the primary reason for what's known as a meat induced alpha-gal allergic reaction.

Alpha-gal is a sugar carbohydrate found in red meats such as beef, pork and lamb. According to the study, positive alpha-gal rates are 32 percent higher in lone star tick population areas as compared to other regions. The central and southern regions of the United States have the highest rates of alpha-gal sensitization due to the lone star tick.

"Blood levels of antibodies for alpha-gal in the human body can rise after a single bite from the lone-star tick," said allergist Stanley Fineman, M.D., ACAAI president. "This can result in allergic symptoms which are usually delayed after meat ingestion and may present as mild hives but may also be a severe, potentially deadly reaction known as anaphylaxis."

The study also found positive rates higher than expected in the north-central and west regions of the country, where the lone star tick is not found.

"These findings suggest that other species of ticks, or possibly human factors, may play a role in allergic reactions to alpha-gal," said Dr. Fineman. "Patients with delayed allergic reactions after eating meats should see an allergist to determine if it is an alpha-gal allergy. The best treatment is strict avoidance of meat. An allergist may also prescribe epinephrine in the event of a life threatening emergency."

Unlike other food allergies, alpha-gal meat allergy can be delayed as long as three to six hours after eating meat. Symptoms range from mild to severe and may include:

• Hives or skin rash
• Nausea, stomach cramps, indigestion, vomiting, diarrhea
• Stuffy/runny nose
• Sneezing
• Headaches
• Asthma
• A severe allergic reaction is known as anaphylaxis, which starts rapidly and may cause death

If you experience an allergic reaction after eating meat, seek emergency medical attention. Follow up with a board-certified allergist who can develop a treatment plan for you and prescribe life-saving epinephrine.