Background:
Preliminary data on the number of tick-borne encephalitis (TBE) cases reported in 2024 from several European countries were previously presented and discussed in the December 2024 Newsletter. By the end of the year, national notification rates indicated a relatively high burden of disease. Final figures for Central Europe—specifically Germany, Austria, and Switzerland—have now been published, either through special reports (Germany and Austria) or on the official website of the Federal Office of Public Health (Switzerland).
Results:
Germany
In 2024, a total of 686 TBE cases were reported in Germany, marking the second-highest annual figure since surveillance began in 2001 (the highest being 718 cases in 2020). This number is nearly double the long-term median of 352 cases per year. Three cases were fatal.
Most cases were reported in Bavaria (266 cases; 47.6%), followed by Baden-Württemberg (172; 30.8%) and Saxony (63; 11.3%). Additional risk areas were identified in Hesse, Thuringia, Brandenburg, Lower Saxony, Saarland, North Rhine-Westphalia, and Rhineland-Palatinate. Three new risk areas were designated in 2024—one each in Lower Saxony, Brandenburg, and Bavaria—bringing the total number of officially classified TBE risk areas to 183, as defined by the Robert Koch Institute. Outside of these zones, sporadic cases were observed across various federal states. Hamburg remains the only federal state without a documented TBE case to date.
Vaccination coverage remains low: 22.1% in Bavaria, 17.1% in Baden-Württemberg, 27.5% in Thuringia, and 17.6% in Hesse. Even in the 63 counties with the highest TBE incidence, vaccination rates were only slightly higher compared to counties with lower incidence. Key barriers to vaccination include low perceived risk of infection and concerns about potential vaccine side effects.
Austria
In 2024, Austria reported 158 hospitalized cases of TBE. An additional 18 cases were diagnosed in outpatient settings. These numbers fall within the typical range observed over the past five years. Most cases occurred in Upper Austria (n=49), followed by Styria (n=22) and Salzburg (n=19).
The youngest patient was two years old (with encephalomyelitis), and the oldest was 86 years old (with meningoencephalitis). More than half of the cases (63.9%) occurred in individuals over the age of 50. No fatalities were reported in 2024.
Switzerland
In 2024, Switzerland recorded 434 TBE cases—the highest number ever reported in the country, slightly exceeding the previous peak of 433 cases in 2020. The national incidence was 4.82 per 100,000 population. Case numbers peaked in June, with a smaller secondary peak observed in October.
Discussion:
The burden of TBE remains high in Central Europe. There is an urgent need to improve vaccination coverage to reduce disease incidence and prevent severe outcomes.
Literature:
Robert Koch-Institut (RKI). FSME-Risikogebiete in Deutschland (Stand: Januar 2025). Epid Bull. 2025;9:3-23. doi:10.25646/13037.2
Raffl S, Stiasny K. Frühsommermeningoenzephalitis (FSME) in Österreich 2024. Vir Ep Inf. 2025;03/25-5. Available from: https://viro.meduniwien.ac.at
Bundesamt für Gesundheit, Bern. FSME (Frühsommer-Meningo-Enzephalitis). BAG-Bulletin, Infectious Diseases Dashboard (IDD). Available from: https://idd.bag.admin.ch
Author: Dr. Michael Bröker
Compiled: March 2025