The lone star tick, notorious for spreading disease and causing a red meat allergy called alpha-gal syndrome, has long plagued the eastern United States.
Now, UC Davis researchers warn it may be edging closer to establishing itself in California.
Their study uncovered seventy-six lone star ticks reported across the state, including recent finds in the Bay Area and San Clemente. While field teams in 2024 and 2025 didn’t recover any during surveillance, climate models show coastal California offers prime conditions for the species.
Experts say the tick isn’t officially established yet, but the risk is real. With climate change and increased movement of animals and people, scientists caution that Californians should stay vigilant, check for ticks after outdoor activities, and report unusual sightings.
Click here to read the study in the journal Ticks and Tick-borne Diseases.
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