Exploring the Ozarks Outdoors: freshare.net

Tick Bites Causing Unusual Allergic Reactions

By Robert J. Korpella

First posted on 08-31-2012


Beside that nasty, itching wound left behind, we most feared Lyme disease or Rocky Mountain spotted fever spread by ticks. Now scientists have linked another problem with tick bites: severe allergic reactions to eating red meat.

The lone star tick, named for the single white dot on its back, is responsible for inducing an allergic reaction in some people after they consume a nice beef, pork or lamb dinner. That reaction has ranged from a breakout of hives all the way up to anaphylactic shock.

imageDr. Scott Commins, assistant professor of medicine at the University of Virginia in Charlottesville, reports he has already seen about 400 such cases along the East Coast and across the mid-South. About 90 percent of the time, a lone star tick bite preceeded the allergic reaction.

Allergies occur when human antibodies attack certain substances, releasing histamines in the body. The result could be swelling, hives or more severe reactions. Lone star tick bites elevate the antibodies that reject a galactose compound in some people. The particular galactose—alpha-gal—is a sugar found in red meats but not in chicken or fish.

Commins said that research has yet to uncover the exact mechanism that makes a lone star tick bite turn into a gastronomical nightmare, but he feels it could be bacteria or another substance in the arachnid’s saliva. He also said it could even be the saliva itself.

Diagnosis has also been an issue since the allergic reaction does not typically occur for 3 to 6 hours after an allergy-sensitive individual ingests red meat. Commins says that may be because the alpha-gal antibody triggers within the tick’s saliva attach themselves onto fat molecules. He said that fat enters the human body’s bloodstream about 3 to 5 hours after eating.

Commins also finds it odd that the allergic reaction is in response to a sugar, observing that most allergies result from proteins. Commins said this might be a clue that will help reveal the bite-to-allergic reaction mechanism.

Comments:

We’re based in Southwest Missouri, Tina. About an hour or so from Bentonville.

By Robert J. Korpella on September 06, 2012 - 9:49 am

A very interesting article, Bob.

By Robert J. Korpella on September 06, 2012 - 9:42 am

Where is your magazine based?  I am in Bentonville, and part of the original research regarding Alpha-gal allergy.

By Tina Hatley Merritt MD on September 05, 2012 - 11:13 pm

Interesting article.  When I saw the header, I thought it would be about the subject of this url - http://www.npr.org/blogs/health/2012/08/29/160272241/mysterious-new-heartland-virus-discovered-in-missouri?ft=3&f=1001&sc=nl&cc=nh-20120830 - also very interesting.

By Bob Ranney on August 31, 2012 - 3:20 pm

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