Page 392 - TBE_Book_V2_2019

Chapter 12b: TBE in Slovakia

Overview of TBE in Slovakia

Table 1: Virus, vector, transmission of TBE in Slovakia

European subtype 1

At present, there are around 50 known endemic TBE foci in Slovakia. A list of
natural foci of TBE in Slovakia was developed by the Public Health Authority of
Slovakia in 2002 directly on the basis of virus isolation data from ticks and
reservoir animals in the years 1964–1997 from the Institute of Virology, Slovak
Viral subtypes,
Academy of Sciences in Bratislava as well as indirectly, by inference about the
distribution 8
site of infection in patients with TBE as reported during 1972–2002.
In recent years there has been a shift of natural TBE foci from the southern to
9
the northern areas of the country, especially in the basin of the river Váh in the
western part of the country, but also in eastern Slovakia. Since 2006, we have
10
observed a slightly increasing trend of TBE incidence.
 Tribeč region (Jarok pri Nitre, Jelenec, Topoľčianky), 1965: Out of 46 blood
and brain samples kept from moles (Talpa europaea), 7 positive isolations of
TBEV were obtained. Therefore, moles can represent not only an important
host animal, but may also be considered a reservoir of TBEV in elementary
11
foci.
 Tribeč region, 1967: Isolation of virus from the blood of Apodemus flavicollis,
12
Clethrionomys glareolus, and Erinaceus roumanicus
Reservoir  Tribeč region, 1967: 2 TBEV strains were isolated from I. ricinus collected on
animals 13
2 Turdus merula
 Lúky pod Makytou, 1981: 5 strains of TBEV isolated from ticks and organs
14
of Apodemus flavicollis (in 15% infected)
 Western Slovakia (6 localities), 1981–1986: 6 TBEV strains isolated from
15
organs of C. glareolus (4), Apodemus flavicollis (1), Sorex araneus (1)
 Záhorská Ves, 1990–1992: 8 TBEV isolates from organs of C. glareolus (6),
16
Apodemus flavicollis (1), Apodemus sylvaticus (1)
The number of infected ticks in endemic areas varies widely from 0.1 to 5%
18
depending on the season and habitat

 Tribeč, 1964: On average, 0.2% ticks were infected by TBEV in the entire
Tribeč region. When only elementary foci were taken into account, this
18
proportion increased to 0.4% (Topoľčianky) and 0.8% (Jelenec)
Infected tick 19
species (%)  Záhorská Bystrica, 1965: 1.7% female ticks infected by TBEV
20
 Devín, 1973: 0.1% nymphs and 1.1% female ticks infected by TBEV
 Slovakia, 1981: In Slovakia there are 2 types of TBEV natural foci – Carpathian
and Pannonian. In Carpathian natural TBEV foci, there were 2.6% ticks
infected by TBEV. In the Pannonian natural TBEV foci, there were 0.1% ticks
21
infected by TBEV

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