A tick that makes people vomit when they eat red meat is spreading across the United States.
Just one bite from the lone star tick, named for the white spot on its back, can trigger a life-long allergy known as alpha-gal syndrome (AGS).
It originates from the alpha-gal sugars the tick ingests when it feeds on mammals, such as mice, rabbits or deer. Then, if the tick moves onto a human, it can inject the sugars into them through its saliva.
Humans do not have alpha-gal in their bodies, so the immune system will fight back and develops anti-bodies.
People with the syndrome report numerous allergic reactions to meat, from anaphylaxis to stomach problems, hives and headaches.
It is often difficult to diagnose as reactions can happen hours after the meat is ingested. The allergy lasts a lifetime and can become worse as time goes on.
The first cases identifying the connection between the tick and syndrome were researched in 2009 after they appeared in the southeastern US.
But the bug has now moved northwards, as far as Washington DC, thanks to a warming climate. Rising temperatures mean that the bug can live through the winter and survive cooler climates.
Between 2010 and 2018, more than 34,000 cases of AGS were reported. Some more serious cases have reported aversions to other animal products, including dairy.
Smell of cooking meat can trigger reaction
Amy Shea, a woman in Georgia, can suffer a reaction from just the smell of meat cooking, according to CBS News.
She must avoid all animal products and check soap and cosmetic packaging for animal-derived ingredients.
Keith Tremel, from Maryland, has to wear gloves to handle red meat to avoid breaking out in a rash after being bitten five years ago.
“Before my diagnosis, I loved bacon cheeseburgers. My wife and two kids both like bacon, and my son enjoys steak, so cooking that for them can be a little bit of torture,” he told the Washington Post.
US health officials have warned people to check themselves carefully when crossing grassy, brushy, and wooded areas during the spring and summer months when the ticks are especially aggressive.