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A Model for Epilepsy of Infectious Etiology using Theiler's Murine Encephalomyelitis Virus
Published on: June 23, 2022
Siberian subtype tickborne encephalitis virus, Finland.
Anu E Jääskeläinen1, Tapani Tikkakoski, Nathalie Y Uzcátegui
1Haartman Institute, University of Helsinki, Helsinki, Finland. anu.jaaskelainen@helsinki.fi
Emerging Infectious Diseases
|December 21, 2006
Summary
Eleven Siberian subtype tickborne encephalitis virus (TBEV) strains were found in Finland. This discovery expands the known geographic range of this tick-borne virus and its primary tick vector, Ixodes persulcatus.
Area of Science:
- Epidemiology
- Virology
- Arthropod-borne diseases
Background:
- Tickborne encephalitis virus (TBEV) is a significant public health concern in Europe and Asia.
- The Siberian subtype of TBEV has historically been documented in Eastern Europe and Siberia.
- Ixodes persulcatus ticks are known vectors of TBEV.
Purpose of the Study:
- To investigate the presence and distribution of TBEV in a previously uncharacterized region.
- To identify the specific subtype of TBEV circulating in the study area.
- To determine the role of Ixodes persulcatus ticks in TBEV transmission in western Finland.
Main Methods:
- Collection of Ixodes persulcatus ticks from a TBEV-endemic focus in the Kokkola Archipelago, western Finland.
- Isolation and identification of TBEV strains from collected tick samples.
- Phylogenetic analysis to determine the subtype of the isolated TBEV strains.
Main Results:
- Eleven strains of Siberian subtype TBEV were successfully isolated from Ixodes persulcatus ticks.
- This finding represents the first report of Ixodes persulcatus ticks and the Siberian TBEV subtype in this geographic area.
- The identified focus is located considerably northwest of the previously known distribution range for both the tick and the virus.
Conclusions:
- The geographic range of the Siberian subtype of TBEV and its vector Ixodes persulcatus extends further northwest than previously documented.
- This expansion has implications for public health surveillance and risk assessment in newly affected regions.
- Further research is warranted to understand the ecological factors driving this range expansion.
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