Page 297 - TBE_Book_V2_2019

Chapter 12b

TBE in Germany

Gerhard Dobler and Ute Mackenstedt

History and Current Situation

The beginning of research on TBE in Germany the prevalence rates vary depending on the
was influenced and inspired by the results and tick stage from 0.1 to 0.5% (nymphs) up to 5%
7,8
developments of TBE research in the former (adult stages). The molecular
Czechoslovakia. There, TBE virus was detected characterization of a number of virus strains
in Czechoslovak Republic in 1948. In Germany, isolated from ticks in Germany shows that so
the first evidence of the presence of TBE virus far all known strains belong to the western
8
was found by Sinnecker and his group in the (European) subtype of TBE virus. Ixodes
1
former German Democratic Republic (GDR). ricinus, the sheep tick, is the most important
The first virus strains were isolated also by vector of TBE virus in Germany. In 2016, TBE
2
Sinnecker’s group in the early 1960s. In the virus was detected for the first time in
former Federal Republic of Germany (FRG) Dermacentor reticulatus in the Federal State of
TBE research started with research on TBE Saxonia. In 2016 and 2017 also for the first
virus in the region of Franconia by Scheid and time in about 50 years two goat milk-borne
3,4
Ackermann. In the region of Lower outbreaks of TBE were registered in Germany
Franconia a virus was isolated which was (districts of Reutlingen, Tübingen, Baden-
called “Zimmern Virus” after the location of Württemberg).
5
the isolation. Unfortunately, all these virus
strains were lost but it can be assumed that In Germany TBE is found mainly in the
they all belonged to the Western (European) southern part, with the federal states of
subtype of TBE virus. Bavaria and Baden-Württemberg comprising
80 to 90% of all reported human cases in
In the 1970s a strong decrease of reported Germany. The annual reported human cases
human TBE cases occurred in the formed range from 200 to >550 (RKI, SurvStat).
endemic areas of the German Democratic Seroprevalence rates before vaccination
6
Republic. In Western Germany, only few programs started in endemic areas in the
studies were conducted on the geographic human population ranged between 3 to 8%
appearance of human TBE cases, mainly led by with high clustering in some human
the company IMMUNO, the first producer of a populations, indicating a highly focal
TBE vaccine in Western Europe. No systematic geographic distribution with the endemic
epidemiological studies are available from this areas. Calculating the incidence of the overall
time. TBE was not reportable during this time. German population is generally low
(<0.1/100.000), but these figures may give a
In 2001, TBE became a reportable disease by strongly underestimated risk for some districts
the new Infection Control Act. From this time in Southern Germany, where the highest
on, reliable data on the prevalence of TBE in incidence rates in Germany can reach
Germany are available. In the era of molecular incidence rates >10/100.000 in particular
detection studies in different areas of districts (e.g. Amberg, Bavaria and
Germany on the prevalence of TBE virus in Ortenaukreis, Baden-Württemberg).
ticks were conducted. In non-engorged ticks

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