News Health & Medicine Three U.S tick species may cause a mysterious red meat allergy The lone star tick isn’t the only one that can trigger alpha-gal syndrome, two cases suggest A bite from a western blacklegged tick may, in rare cases, cause a red meat allergy known as alpha-gal syndrome. CDC By Meghan Rosen 1 hour ago Cathy Raley’s first bout of hives woke her in the middle of the night with itchy bumps that crept up her arms and spread to her legs and back. Her second bout took her to the hospital. It was a June afternoon in 2017, and she was getting ready to take her dog, Jake, on a hike. The hives started suddenly, when she was about to load Jake into the car, but this time was different, Raley says. Her tongue was swelling, and her throat was getting tight. “That’s when I called 911.” Sign up for our newsletter We summarize the week's scientific breakthroughs every Thursday.