Tick-borne α-gal allergy to red meat surges worldwide, scientists seek answers

A tick-transmitted allergy to the sugar α-gal, which can cause severe reactions to red meat and dairy, is increasing globally, and researchers still lack a cure.

Scientists explain that bites from ticks carrying the sugar α-gal can sensitize individuals, leading to IgE antibodies that react to red meat and dairy. The allergy, known as α-gal allergy, can cause severe anaphylaxis and has already claimed at least two lives. Incidence is rising sharply: Australia reports over 700 cases per 100,000 in high-risk zones with a 22 % annual increase since 2020; the U.S. CDC estimates up to 450,000 affected, with about 15,000 new diagnoses each year, especially where lone-star ticks thrive; Japan shows up to 4.9 million sensitized, while Denmark’s sensitization doubled from 1990 to 2016.

Researchers link the surge to warming climates expanding tick habitats and expanding deer hosts such as white-tailed and roe deer. Diagnosis remains challenging due to delayed, vague gastrointestinal symptoms, and there is currently no approved treatment, spurring calls for targeted therapies from experts like Benjamin Casterline at the University of Missouri and Thomas Platts-Mills at the University of Virginia.