Background
The number of reported TBE cases is fluctuating from year to year. For 2022, reports have recently been published in German for the German speaking countries in Central Europe. The aim of this newsletter is to summarize these data for the international readership of the TBE News.
Results
Austria
In 2022, a total of 179 patients have been hospitalized in Austria, and, in addition, 13 patients infected by TBE virus received ambulatory treatment.
While the number of reported TBE cases were between 46 to 116 from 2007 to 2017, there was a significant increase of cases observed since 2018.
Most TBE patients lived in Upper Austria, followed by Tyrol and Salzburg. TBE cases were reported from April to December with a maximum from May to August. The patients’ age ranged between 1 to 93 years. 12.3% of all infections were in children under 15 years of age. 77 patients had a mild disease course (meningitis of infection with fever), while 89 patients had a severe neurologic infection (meningoencephalitis/myelitis/radiculitis). Two TBE patients (63 and 86 years of age) died.
Germany
A total of 546 TBE cases have been notified by the Robert Koch-Institut (RKI) in 2022 (421 cases in 2021). In 52% of these cases, the patients had neurological manifestations and were suffering from meningitis, encephalitis or myelitis. Two patients died. Most individuals became infected in Bavaria (n=226, 47.1%), followed by Baden-Wuerttemberg (n=179, 37.3%) and Saxony (n=33, 6.9%). Some patients had most probably acquired TBE virus infection by consumption of non-pasteurized milk or milk products.
Three districts have been assessed as new risk region. Hence, 178 districts are now TBE risk regions according to the definition of the RKI, most of them located in Bavaria and Baden-Wuerttemberg (southern Germany). Sporadic TBE cases have been notified in all federal states over the past few years except Bremen and Hamburg.
Vaccination rates remained low. In risk regions with an incidence in the upper tercile, the vaccination rate was only about 23%. In the middle tercile, it was about 20%, followed by about 19% in the lower tercile.
Switzerland
In Switzerland, TBE surveillance started in 1984, and TBE became a notifiable disease in 1988. No annual report is published by the Federal Office of Public Health; however, TBE cases are reported weekly and are listed in the BAG Bulletin.
In Switzerland, a total of 393 TBE cases have been reported in 2022, which was the second highest number after the peak in 2020 with 454 cases (285 cases in 2021).
Conclusion
2022 can be characterized as a year with a significantly high number of reported TBE cases in Central Europe / the German speaking countries.
The incidence in or close to the Alps (Austria, Switzerland, Bavaria, Baden-Wuerttemberg) demands attention, and activities to increase awareness about TBE and the benefits of vaccination are warranted.
Literature
Stiasny K
Frühsommermeningoenzephalitis (FSME) in Österreich 2022 [Tick-borne encephalitis (TBE) in Austria 2022]
Vir Ep Inf. Nr. 03/23: 5-6
www.virologie.meduniwien.ac.at
Robert Koch-Institut (RKI)
FSME-Risikogebiete in Deutschland (Stand: Januar 2023) [TBE risk regions in Germany, as at January 2023]
Epid Bull. 2023;9:3-22. doi.org/10.25646/11176
www.rki.de
BAG-Bulletin 1+2/2023, Seite 7
Meldungen Infektionskrankheiten [Notification on infectious diseases]
Stand am Ende der 52. Woche (03.01.2023)
www.bag.admin.ch/bag-bulletin
Author: Dr. Michael Bröker
Michael Bröker is a microbiologist/biochemist by training. He has more than 35 years of experience in the field of biotechnology and vaccinology while working for various pharmaceutical companies. He also worked as curator and expert in committees of foundations, scientific boards and associations as well as for companies.
Compiled: March 2023