Pathogen tests on 707 non-engorged adult female deer ticks submitted in 2024 found 51% carried Borrelia burgdorferi, the bacterium that causes Lyme disease.
Marshfield Clinic Research Institute gathered the samples through its Tick Inventory via Citizen Science database, launched in 2024 to map tick species ranges and the pathogens carried by blacklegged ticks across the Upper Midwest.
Wisconsin health officials say reported Lyme disease cases have quadrupled over the past 20 years, and deer ticks can also spread anaplasmosis, babesiosis, ehrlichiosis and other illnesses.
Researchers said shifting climate conditions are making some tick species more prevalent or bringing them into new areas, increasing the importance of tracking where and when exposure risk is changing.
With Lyme disease surging, are current prevention strategies enough to stop the predicted 2026 spike in cases?
One tick bite can now transmit multiple diseases. Is the standard antibiotic treatment still effective against these dangerous co-infections?