Red meat and gelatine allergy link to tick bites

tick

A link between tick bites and the development of delayed onset allergy to red meat has recently been discovered by Australian and American allergists.

Reactions can range from mild stomach pains to vomiting and abdominal cramps, hives or breathing difficulties and even life-threatening anaphylaxis.  Unlike most food allergies, the symptoms are typically delayed three to six hours after an affected person eats mammalian meat such as beef, lamb, pork, goat or kangaroo and often occur in the middle of the night. Since the tick bite responsible for the allergy may have occurred weeks or months before, it can be difficult for affected people to recognise the cause of their problem.

Some people who are allergic to red meat also develop allergies to meat-derived gelatine that is used in hundreds of commercial food products such as marshmallows, jellies and capsules.

Affected people have been reported in the southern, eastern and central United States, and tick-endemic regions on the east coast of Australia. There have also been cases in Sweden, France and Spain.

The condition was first reported by Associate Professor Sheryl van Nunen, a clinical immunology specialist at Royal North Shore Hospital who sees two new cases per week. Thousands of people have been diagnosed in the US and the condition is expected to become more common as tick hosts such as deer and bandicoots increase in suburban areas, possibly due to global warming.

The condition has been linked to a particular sugar called alpha-gal. American researchers report that many affected individuals have negative allergy skin prick tests to meat, making it hard to obtain a diagnosis. However, with the recent development of IgE alpha-gal tests, the clinical diagnosis can be confirmed in the laboratory. The only treatment is avoidance and carrying a precautionary Epi-pen.

In the past, sufferers have had trouble getting doctors to believe them. “Two patients have recently come to see us and reported that they had told us the same story 15 and 18 years previously,” said allergy researchers Drs. Platts-Mills and Commins from the University of Virginia. Dr Platts-Mills himself was affected during the intervening years.

Some examples of difficult-to-diagnose conditions include an 8 year old who had debilitating, chronic stomach problems for years every time he ate meat after a school camp where several students were bitten by ticks. After his diagnosis, five years later he became violently ill after toasting marshmallows around the fire with friends because the marshmallows contained beef gelatine.  Another woman struggled for four years with what she thought could be chronic fatigue and what some doctors even suggested ''was in her head''.

In 2006, I received an email on the subject of kangaroo meat allergy from a woman named Julie. “I don't think I have any allergies or intolerances (well not that I've noticed in the past) but recently, I have had kangaroo meat on a few occasions and have been sick each time within about 3 hours”, she wrote. “I therefore assume that I have developed an allergy (intolerance?) to kangaroo meat. Could this be so and why?” On the third occasion, she had been violently ill for a few hours. At the time I had no suggestions.  Julie, I hope you have now found your answer.

More information

Tick Induced Allergies and Awareness  www.tiara.org.au

University of Virginia Mammalian Meat Allergy blog http://allergytomeat.wordpress.com/frequently-asked-questions/

Ticks that spread red meat allergy, Wall Street Journal, June 14, 2013 http://online.wsj.com/news/articles/SB10001424127887324634304578537203916053308

Just one bite: ticks and allergies on the North Shore, Sydney Morning Herald, December 27  http://www.smh.com.au/nsw/just-one-bite-ticks-and-allergies-on-the-north-shore-20131226-2zxru.html#ixzz2pkhmKeBq

Van Nunen SA et al. An association between tick bite reactions and red meat allergy in humans. Med J Aust. 2009 4;190(9):510-1. http://www.ncbi.nlm.nih.gov/pubmed/19413526

Commins SP et al. The relevance of tick bites to the production of IgE antibodies to the mammalian oligosaccharide galactose-α-1,3-galactose. J Allergy Clin Immunol. 2011 May;127(5):1286-93.e6. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3085643/

Mullins RJ et al. Relationship between red meat allergy and sensitization to gelatin and galactose-α-1,3-galactose. J Allergy Clin Immunol. 2012;129(5):1334-1342.e1. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3340561/

Wolver SE and others.  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. J Gen Intern Med. 2013;28(2):322-5.  http://www.ncbi.nlm.nih.gov/pubmed/22815061

Commins SP et al. Delayed anaphylaxis to red meat in patients with IgE specific for galactose alpha-1,3-galactose (alpha-gal). Curr Allergy Asthma Rep. 2013 Feb;13(1):72-7. http://www.ncbi.nlm.nih.gov/pubmed/23054628