Two additional tick species in the U.S. have been found capable of transmitting red meat allergy, or alpha-gal syndrome.

A new invasive tick species was recently found in St. Louis County, with more sightings expected this spring and summer.

Until recently, scientists thought a rare and potentially deadly meat allergy was transmitted by just one species of tick found in the U.S. — the lone star tick (Amblyomma americanum).