Invasive fire ants with a nasty bite are limiting the spread of a dangerous meat allergy, new research suggests. But it’s not all good news, as the ants themselves can also cause severe allergic reactions.
University of Virginia School of Medicine researchers and their collaborators made the discovery while seeking to understand the scope of the “alpha-gal” meat allergy in the United States. Spread by the bite of the lone star tick, the allergy causes people to develop potentially severe allergic reactions to mammalian meat, including beef and pork.
The allergy is commonly seen throughout the Southeast, the Mid-Atlantic and the Midwest, but rarely in the Gulf Coast and Texas. That is likely caused by the steady expansion of fire ants accidentally imported from South America in the 1930s, the researchers conclude.
But the ants are no heroes, as their bites can be very painful and cause severe allergic reactions. In some cases, the bites can cause life-threatening anaphylaxis. That’s in addition to the dangers the ants pose to animals and crops. And the strong-jawed insects are marching relentlessly northward.
“We did not set out to study fire ants, but when the number of alpha-gal cases in the Gulf Coast was consistently lower than we expected, the fire ant emerged as an interesting explanation,” said UVA researcher Behnam Keshavarz, a co-first author of a new scientific paper outlining the discovery.
Mapping Out the Alpha-Gal Meat Allergy
The meat allergy was first identified more than a decade ago by UVA’s Dr. Thomas Platts-Mills, an internationally renowned allergist. Since then, he and his colleagues have shed light on how and why the tick’s bite causes people to develop allergic reactions to a particular sugar, alpha-gal, present in meat and other mammalian products. The symptoms can include itchy rashes, nausea and difficulty breathing. Severe reactions can progress to anaphylaxis if untreated.
Until now, there has been little examination of the geographic scope of the allergy in the United States. The UVA researchers set out to change that. They surveyed allergists across the country to map out cases of the meat allergy. They also tested blood samples from two different geographic areas where it was particularly prevalent. The latter was important to show that the allergy is “immunologically similar” across the country.