The Tick That Hunts Down Its Hosts—Including Us

Alpha-gal may sound like a nickname from a teen movie, but it’s actually a sugar molecule found in most mammals—just not in humans. When people are exposed to it, usually via a tick bite, they can develop an allergy that’s later triggered by eating meat. The idea of developing a meat allergy from a tick bite can sound far-fetched, but Burkhard Bilger carefully walks us through the science and introduces us to the people whose lives have been transformed by alpha-gal syndrome. After reading his account, you may find yourself anxiously checking for ticks after every brush with grass.

Roden-Reynolds is thirty-three and has been the island’s public-health biologist for four years. To a hungry tick, he must have been an appetizing sight: tall, stout, and soft-featured, with pale red hair and eyebrows. His cheeks and hands were flushed pink with blood beneath the skin. But he knew better than to expose his other body parts. He was covered from neck to boots in fabrics soaked with permethrin—a pesticide modelled on the toxic pyrethrin found in chrysanthemum flowers. Had one of these ticks crawled up the cuff of his pants, it would have been dead before it reached his belt.