Southern Illinois Alpha-Gal Cases Rise as Lone Star Ticks Spread Across 10 High-Risk Counties
Updated
Updated · NPR Illinois · Jun 18
Southern Illinois Alpha-Gal Cases Rise as Lone Star Ticks Spread Across 10 High-Risk Counties
3 articles · Updated · NPR Illinois · Jun 18
Summary
Southern Illinois is seeing a rise in alpha-gal syndrome, with a 2025 University of Illinois study placing the state among the top 13 for increasing cases and identifying 10 southern counties as lone star tick hotspots.
At least 90 cases were estimated in every southern Illinois county, while the CDC says more than 110,000 suspected U.S. cases were reported from 2010 to 2022 and as many as 450,000 Americans may be affected.
Researchers say expanding tick populations and a longer active season—now extending into winter in Illinois—are driving the risk, with a 2020 survey finding lone star ticks made up 80% of ticks collected in 11 southern counties.
Diagnosis still lags because many doctors miss the condition: a recent survey found only 25% of medical professionals had heard of alpha-gal syndrome and just 12% knew a diagnostic blood test exists.
Illinois last year enacted the TICK Act, requiring reporting of new alpha-gal diagnoses and directing statewide public-awareness efforts as patients describe major disruptions to diet, travel and daily life.