With rising temperatures in spring, tick activity increases significantly. Due to fewer frost days, ticks now exhibit heightened winter activity as well. This results in a nearly year-round risk of transmission of TBE (tick-borne encephalitis), Lyme disease, and other pathogens. Interestingly, TBE cases are almost always associated with larger river systems—a phenomenon that remains unexplained to this day.
Our district has long been one of the high-risk areas for TBE in Bavaria. Each year, between 240 and 260 new cases are reported in Bavaria. The actual number is likely much higher, as 70 to 95% of infections are either asymptomatic or do not progress to the second stage of the disease, which involves meningitis.
Unfortunately, unlike bacterial Lyme disease, no specific treatment is currently available for the viral TBE.
Ticks carry the TBE virus in their saliva, meaning transmission can only be prevented if the tick is removed before it attaches. This makes protective vaccination particularly important for at-risk individuals. Vaccination rates are highest among children and adolescents in Bavaria, but the overall vaccination rate is only around 22%.
The number of reported Lyme disease cases is significantly higher than TBE, with 3,000 to 4,000 cases annually in Bavaria in recent years. Borrelia, the spiral-shaped, metabolically slow bacteria responsible for Lyme disease, reside in the tick’s gut. Transmission is only possible if the tick has sufficient time to feed, typically several hours.
Over the past decades, there have been repeated attempts to develop reliable vaccines against Lyme disease. Currently, Valneva, in collaboration with Pfizer, is developing a vaccine designed to protect against all six variants of European Lyme disease. According to a press release from the companies in December 2024, the vaccine is planned for market launch in Europe in 2026.
The vaccine targets proteins on the surface of Borrelia bacteria. The resulting immune response can neutralize and eliminate Borrelia in the bloodstream. In vaccinated individuals, transmission from ticks to humans is also prevented by antibodies in the blood that destroy Borrelia in the tick’s gut. However, studies indicate that Borrelia in joints are only inadequately addressed by the vaccine. Therefore, the vaccine primarily protects against new infections, while antibiotics are more suitable for treating existing Lyme disease cases. (Source: RKI)