Tick-borne encephalitis is the clinical disease caused by tick-borne encephalitis virus (TBEV), which is identified in the sources as a flavivirus and an arboviral etiologic agent [1][2]. The condition is framed as a tick-borne viral disease of major relevance in Europe and Asia, with reported increases in incidence and geographical range in recent years [1][2]. The provided sources do not add further source-backed detail on viral subtype distribution beyond noting that mortality depends on subtype [2].
Disease overview
Tick-borne encephalitis
蜱传脑炎
Evidence-backed informationEN 6/7 applicable sections · ZH 6/7 applicable sectionsUpdated Sep 3, 2026
Tick-borne encephalitis is a viral arboviral disease caused by tick-borne encephalitis virus (TBEV), an agent described as one of the most important tick-borne viral diseases in Europe and Asia [1][2]. It is an emerging public-health problem with increasing incidence and expanding geographic range, and annual human case counts have been estimated at 10,000 to 15,000 [1][2]. Source-backed detail on diagnosis and treatment is not included here, but prevention is emphasized through immunization and protection against tick bites [1].
Read the full clinical and epidemiological profile7
Human TBEV infection may be asymptomatic, or it may present with symptoms ranging from mild influenza-like illness to severe neurological disease [1][2]. One review describes a characteristic biphasic course, beginning after a short incubation period with a viraemic phase marked by non-specific flu-like symptoms, followed after an asymptomatic interval of 2–7 days by a neurological phase in more than half of patients [2]. Neurological involvement is usually central and more rarely peripheral, and the sources note that after acute disease a minority of patients have long-term neurological deficits [2]. A post-encephalitic syndrome is reported in 40%–50% of patients and is said to impair daily activities and quality of life [2]. Mortality is described as low, around 1% of confirmed cases, depending on viral subtype [2].
TBEV is reported as commonly found in at least 27 countries across Europe and Asia, and it is described as one of the most important tick-borne viral diseases in these regions [1][2]. The disease is characterized as emerging, with steadily increasing case numbers over recent decades and a rising incidence in more than half of the European countries analyzed in recent studies [1][2]. The sources estimate 10,000 to 15,000 patients annually and state that cases in Europe are reported every year [2][1]. In nature, ticks and small mammals are said to help maintain the virus, and the virus can also infect dogs, horses, cattle, and small ruminants [1].
Humans are described as incidental hosts, with infection occurring primarily through the bite of an infected tick [1][2]. Less common transmission is reported through the alimentary route after consumption of unpasteurized milk or milk products from infected animals, and one review also mentions aerosols as a much less common route [1][2]. The sources further note transmission between ticks, animals, and humans, with ticks and small mammals contributing to maintenance in nature [1].
They do indicate that humans are incidental hosts and that exposure occurs through infected tick bites or, less commonly, contaminated milk or milk products, so persons with such exposures are the main source-backed risk context [1][2].
The sources identify immunization and protection against tick bites as critical measures for preventing tick-borne encephalitis [1]. They also imply exposure control through avoidance of unpasteurized milk or milk products from infected animals, given the alimentary route of transmission [1][2]. No further source-backed detail on vaccine schedules, specific repellents, or other prevention protocols is available in the supplied material [1][2].
- 1Kwasnik M et al. Tick-Borne Encephalitis-Review of the Current Status. J Clin Med. 2023 Oct 18. PMID: 37892741. doi: 10.3390/jcm12206603.PubMed: https://pubmed.ncbi.nlm.nih.gov/37892741/
- 2Chiffi G et al. Tick-borne encephalitis: A comprehensive review of the epidemiology, virology, and clinical picture. Rev Med Virol. 2023 Sep. PMID: 37392370. doi: 10.1002/rmv.2470.PubMed: https://pubmed.ncbi.nlm.nih.gov/37392370/
- A84
- 1D49
Coverage
Reporting countries and regions
AustriaAT
BelgiumBE
BulgariaBG
CroatiaHR
CzechiaCZ
DenmarkDK
EstoniaEE
FinlandFI
FranceFR
GermanyDE
GreeceGR
HungaryHU
IcelandIS
IrelandIE
ItalyIT
JapanJP
LatviaLV
LiechtensteinLI
LithuaniaLT
LuxembourgLU
MaltaMT
NetherlandsNL
NorwayNO
PolandPL
PortugalPT
RomaniaRO
SlovakiaSK
SloveniaSI
South KoreaKR
SpainES
SwedenSE
SwitzerlandCH
United KingdomGB
Trends by reporting country
Monthly patterns over time
Research Radar
Recent related research
Peer reviewedOpen accessTick-borne encephalitis
DOI 10.1016/j.ttbdis.2026.102673 ↗Cognitive outcome in relation to cerebrospinal fluid markers of neuronal and glial cell damage: A prospective study of tick-borne encephalitis.
Ticks and tick-borne diseases
Fatal European subtype tick-borne encephalitis in a fully vaccinated immunocompetent child: a case report with viral sequencing.
BMC infectious diseases
Tick-Borne Encephalitis Vaccine Effectiveness and Impact in Slovenia, 2019-2024.
Pathogens (Basel, Switzerland)
Tick-borne encephalitis vaccination coverage among outdoor workers in Sweden: a nationwide survey
Vaccine
High burden of autochthonous arboviral infections during the summer season in Verona province, Italy, during 2025
Journal of Infection
Showing 5 of 14 related publications.
Literature links are provided for discovery and do not alter or validate the surveillance series above.
Data access
Page dataset index with source links and update metadata.
Official sourcesAuthority, cadence, notes37
Austria AGES Radar for Infectious Diseases
Austria
AGES Radar monthly national source. Internal ingestion retains native categories; public release is disabled pending licence review.
ECDC Surveillance Atlas — Belgium Annual Baseline
Belgium
Belgium annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Bulgaria Annual Baseline
Bulgaria
Bulgaria annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
Switzerland FOPH IDD
Switzerland
Switzerland FOPH/BAG IDD mandatory reporting API normalized to national case rows. Monthly series may use the dashboard CHFL aggregate where CH-only monthly series are not exposed.
ECDC Surveillance Atlas — Czechia Annual Baseline
Czechia
Czechia annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
Germany RKI SurvStat 2.0
Germany
RKI SurvStat national weekly notification export; raw ZIP exports are retained and recent weeks are overwritten for revisions.
ECDC Surveillance Atlas — Denmark Annual Baseline
Denmark
Denmark annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Estonia Annual Baseline
Estonia
Estonia annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Spain Annual Baseline
Spain
Spain annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
Finland THL Infectious Diseases Register
Finland
Finland THL Infectious Diseases Register national monthly case counts. The current month is ingested as provisional and the latest three months are refreshed for source revisions.
ECDC Surveillance Atlas — France Annual Baseline
France
France annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — United Kingdom Annual Baseline
United Kingdom
United Kingdom annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Greece Annual Baseline
Greece
Greece annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Croatia Annual Baseline
Croatia
Croatia annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Hungary Annual Baseline
Hungary
Hungary annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
Ireland HPSC Notifiable Diseases Hub
Ireland
Ireland HPSC national weekly notifiable-disease totals from the official ArcGIS FeatureServer. Internal ingestion is enabled; public release remains disabled pending written redistribution permission.
Iceland Directorate of Health Annual Dashboard
Iceland
National annual case notifications by disease. Published values can be revised retrospectively and remain annual period totals.
Iceland Directorate of Health STI Dashboard
Iceland
Monthly STI diagnosis facts from laboratory and registry surveillance; the official dashboard is published on a quarterly schedule.
Iceland Directorate of Health Respiratory Dashboard
Iceland
ISO-week respiratory diagnosis counts. Hospitalizations, samples, and vaccination indicators are separate measures and are not counted as diagnoses.
Iceland Directorate of Health Historical Registry
Iceland
Historical official registry tables for 1997–2021, with annual totals and disease-specific monthly notification facts retained at source grain.
Iceland Directorate of Health Legacy ICD Monthly
Iceland
Historical Saga EHR ICD encounter counts for 1997–2020. This clinical measure is non-comparable with registry notifications and is kept separate.
ECDC Surveillance Atlas — Italy Annual Baseline
Italy
Italy annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
JP NIID Weekly
Japan
Japan weekly infectious disease surveillance via NIID/JIHS.
Korea KDCA EID
South Korea
Korea KDCA notifiable infectious disease OpenAPI or portal/KOSIS downloads aggregated to national monthly notification counts.
ECDC Surveillance Atlas — Liechtenstein Annual Baseline
Liechtenstein
Liechtenstein annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Lithuania Annual Baseline
Lithuania
Lithuania annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Luxembourg Annual Baseline
Luxembourg
Luxembourg annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Latvia Annual Baseline
Latvia
Latvia annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Malta Annual Baseline
Malta
Malta annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Netherlands Annual Baseline
Netherlands
Netherlands annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
Norway FHI MSIS Statistics Bank
Norway
Norway FHI MSIS national monthly notifications from the official Allvis frontend API; adapter contract checks guard the unversioned endpoint.
ECDC Surveillance Atlas — Poland Annual Baseline
Poland
Poland annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Portugal Annual Baseline
Portugal
Portugal annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Romania Annual Baseline
Romania
Romania annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
Sweden Public Health Agency SmiNet
Sweden
Sweden SmiNet national monthly reported cases from the official Public Health Agency statistics pages; public release is enabled with closed-month publication and revisable recent-month refreshes.
ECDC Surveillance Atlas — Slovenia Annual Baseline
Slovenia
Slovenia annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.
ECDC Surveillance Atlas — Slovakia Annual Baseline
Slovakia
Slovakia annual Member-State reported case counts from the ECDC Surveillance Atlas. Missing topic/year cells remain unknown and published zeroes are preserved. Data provided by ECDC based on data reported by EU/EEA Member States.