Scientists uncover genetic weak spot to combat deadly tick-borne encephalitis

Scientists may have found a way to tackle tick-borne encephalitis (TBE), a serious viral infection spread by ticks. Researchers at the Medical University of Graz identified a key gene in the virus that, when blocked, drastically cuts its ability to multiply. The breakthrough offers hope for future treatments in a disease that currently has no specific antiviral cure.

TBE poses a growing threat, with cases rising sharply in parts of Europe. Switzerland and Liechtenstein reported 503 infections in 2025 alone—more than double the number from 2016.

TBE causes severe inflammation of the brain and nervous system. Around half of hospitalised adults never fully recover, while one in ten suffer long-term paralysis. The disease also carries a mortality rate of roughly one percent.

Most infections in Switzerland and Liechtenstein occur in June and July, when ticks are most active. Austria's risk zones—Lower Austria, Styria, and Burgenland—also see fluctuating case numbers, with these regions remaining hotspots for transmission. The Graz team's discovery centres on a genetic weak point in the virus. By targeting this gene, they significantly reduced its ability to replicate in lab tests. However, further studies are needed to confirm whether blocking the gene improves patient outcomes in real-world cases. If successful, the research could pave the way for the first targeted treatment against TBE. Currently, doctors can only manage symptoms, as no antiviral therapy exists for the infection.

The findings mark a potential turning point in the fight against TBE. With cases climbing across Europe, a treatment based on this genetic insight could reduce severe complications and save lives. Researchers now aim to test the approach in clinical trials to assess its real-world effectiveness.