You've heard of Lyme disease, one of several diseases caused by tick bites. Now research reveals how a bite from the lone star tick may cause red meat allergy.

Lone Star Tick Image - CDC

Unlike food allergies to peanuts and milk, which are triggered by certain proteins, red meat allergy may be triggered by alpha-gal, a carbohydrate released in the lone star tick’s saliva, according to the research.

When an exposed person eats red meat, such as beef, lamb or pork, which contain sugars similar to alpha-gal, he or she experiences an allergic reaction, perhaps anaphylaxis, usually within 3 to 6 hours. Symptoms include swelling, hives, and difficulty breathing. Eating poultry, fish and chicken does not cause the reaction, according to sources.

Alpha-gal tests are now available making it easier for a person bitten by the lone star tick to receive a diagnosis. Symptoms of any tick bite may include a rash, fever, headache, joint or muscle pains, or swollen lymph nodes within 30 days of exposure.

Tick-borne illnesses may be prevented by avoiding dense woods and brushy areas, using insect repellents containing DEET or permethrin, wearing long shirts, pants and socks, and performing tick checks after outdoor activity.

According to the Centers for Disease Control and Prevention (CDC), the lone star tick has proliferated in recent decades. It's native to southeastern United States, but large numbers of lone star ticks have been reported as far north as Maine and as far west as central Texas and Oklahoma.


Centers for Disease Control and Prevention (CDC)

News reports

Wolver et al. "A Peculiar Cause of Anaphylaxis: No More steak?: The Journey to Discovery of a Newly Recognized Allergy to Galactose-alpha-1,3-galactose Found in Mammalian Meat." Journal of General Internal Medicine. July 20, 2012.

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Published: 02 Aug 2012

Last Modified: 15 Sep 2015