Tick Borne Disease- Alpha- Gal Allergy
By Josh Palumbo
To be in the center of a bullseye is never the desired location. Whether you are a deer during hunting season or a soldier in war, the bullseye is the place to avoid. It appears Wintergreen and the surrounding locales have found themselves squarely in the proverbial bullseye of a tick borne epidemic.
A cohort of Wintergreen residents, as well as a few in the Rockfish Valley area, have found themselves being poked and prodded by immunologists at UVA due to allergic reactions to tick bites or more specifically the Lone Star tick. To make things worse, the cause of the allergic reaction…red meat. To those non-vegetarians, a perfectly cooked medium-rare steak is divine. To these residents, it has caused symptoms ranging from vomiting, cramps, hives and even anaphylaxis. How can a tick cause the human body to reject a beloved food source? The answer is a sugar known as alpha-gal, found in all non-primate mammals including some of our favorite food sources such as cows, pigs and sheep.
Studies of the alpha-gal allergy began in Australia in the late 1990’s due to strange cases of anaphylaxis caused by their local culprit, the paralysis tick. The allergy was found in central Virginia in 2006 by UVA allergy specialist Dr. Thomas Platts-Mills. He discovered the tick connection while studying severe allergic reactions to the drug cetuximab, in which the alpha-gal sugar was present. They moved towards ticks as the culprits when they noticed that only cancer patients from the southeastern “tick-belt” states had the reaction. They began questioning patients on tick exposure and the link was made. Dr. Platts-Mills became a case study himself after a fateful hike in the Blue Ridge. He returned to find lone star tick larvae attached to his ankles and sure enough he tested positive for the antibodies to alpha-gal. Months later after a meal of lamb he awoke to a covering of hives.
Researchers believe the allergy develops as follows: the tick bites and injects alpha-gal into the body which causes our immune system to release immunoglobulin E (IgE) antibodies. These antibodies prompt the release of histamines to fight the allergen. A few weeks later, the person eats red meat. For a few hours, nothing happens. Then, hives appear followed by swelling on the face, a drop in blood pressure and in some cases, anaphylaxis. The body, which had been sensitized to alpha-gal by the tick bite, overreacted to the meat’s alpha-gal and flooded the body with IgE antibodies. The reaction is delayed by 3-6 hours because alpha-gal is most concentrated in animal fat, which takes hours to digest.
The alpha-gal allergy does not develop in every person bitten by the lone star tick. Researchers are still investigating a variety of correlating factors among those with the allergy. One connection is genetic predisposition. Cases seem to run in families. The UVA researchers have father-daughter pairs, mother-son and sets of cousins in the case study thus suggesting a link to a genetic inclination. A Wintergreen resident with the allergy suggested a correlation between those with severe reactions to mosquito bites with those affected by the allergy at Wintergreen.
How is a property owner at Wintergreen to respond to the fact we have a new tick born ailment in our midst?
From an individual perspective, showing due diligence when we enter the environment is a good start. Here are some smart ways to lessen your chances for an encounter with the lone star tick: wear light colors, tuck your pants into your socks, use a Permethrin tick-repellant product, do a thorough skin check when you come inside, and wash the clothes you had on once you finish your excursion.
From a community perspective, the deer population rise needs to be restrained and brought to more sustainable numbers. The main carriers of the lone star tick are deer and turkey. Deer, being the primary vector at Wintergreen, are at their highest population level since 2007 in Stoney Creek. Last year’s bumper acorn crop and the suspension of the deer removal program at Wintergreen have coincided to create a burgeoning deer population in the valley. Three Wintergreen residents have developed the meat allergy on tiny Blue Chicory Lane alone. This suggests the environment is supporting pockets of robust populations of deer and thus the lone star tick.
Research shows deer herd reduction measures that remove less than 50% of the estimated population typically do not provide significant relief from density-related problems (Creacy, 2006). The Nature Foundation does a semi-annual deer survey focusing on the developed portion of Wintergreen which constitutes approximately 5,000 acres. Using development acreage at Wintergreen, Wintergreen has approximately 283 deer in the developed community. WPOA has been advised that 50% of the population should be targeted for removal (140 deer), with the focus being entirely on Stoney Creek.
Being in the bullseye is the problem. The obvious solution is to get out of the bullseye. A step in the right direction for Wintergreen is to lower the deer population in the development. In addition, each property owner is to show due diligence on each excursion into the environment. These efforts are excellent ways to slow the spread of the alpha-gal allergy in our community.
For more information on tick safety, read our Hiking Tips article below.
May 16, 2019 at 9:27 am
Sure, it is important to get the word out on such diseases and we do appreciate being included in the credit as source of information!