Page 422 - TBE_Book_V2_2019

Chapter 12b

TBE in Switzerland

and Liechtenstein

Daniel Desgrandchamps and Klara M. Posfay-Barbe

History and Current Situation

The first serological reports of tick-borne for the cantons of Geneva and Ticino – as an
encephalitis (TBE) in Switzerland date back to at-risk area in which TBE vaccination is recom-
the early 1970s [T. Krech. Dissertation, Univer- mended for all individuals with possible
2
sity of Berne, 1980]. Surveillance started in exposure (both as residents or as visitors),
1984, and TBE became a notifiable disease in see Figure 3c.
1988. Most cases are reported between April
and October with a tick bite exposure below Currently, vaccination is generally recommend
1,2
an altitude of 1500-2000 meters. -ed and reimbursed by health insurance for
individuals older than 6 years of age living in
Tick-borne encephalitis virus (TBEV) has not or visiting endemic regions. In children aged 1-
been identified in ticks from all regions of the 5 years, the indication shall be based on
country. This explains why human cases are individual considerations. Unlike in other
mainly found in endemic but not in all regions. countries and in contrast to the label, a
Most cases occur in the northeast of the booster dose is recommended every 10 years
3
country, but in recent years, new endemic only.
regions have been detected in western (Vaud)
and south-western Switzerland (Valais), which Between 2000 and 2018, the Federal Office of
suggests that TBE has become endemic almost Public Health has received between 52 annual
in the entire country. reports of TBE cases in 2002 (incidence
0.7/100,000), and 376 cases in 2018
In 2013, a procedure allowing for the (incidence 4.4/100,000). The number of cases
definition of regions with a local TBE fluctuated considerably from year to year; the
vaccination recommendation had been adopt- highest average value was 24.8/100,000
3
ed for Switzerland and Liechtenstein. Data (2018) in the canton of Uri in central
from cases notified over the last 10 years Switzerland. So far, only 10 out of 26 cantons
(“high risk areas”, Fig. 3a) were combined with plus Liechtenstein have notified at least 1
data from the historical map of Swiss endemic patient every year.
4
regions and “natural clusters”. The resulting
Swiss map was used until 2018 for the As elsewhere in Europe, the proportion of
definition of regions where TBE vaccination is ‘mild cases’ is lower and the number of more
recommended for exposed people (Figure 3b). serious cases higher with increasing age.
However, more serious disease pictures like
However, in view of the increasing numbers of meningoencephalitis have also been reported
reported TBE cases in recent years, Swiss and in children below the age of 6 years over the
Liechtenstein health authorities decided in last years (E. Altpeter, FOPH, personal
2019 to consider the entire countries – except communication). Less than half (45%) of

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