Tick-borne Encephalitis Virus Research in Limousin (VITAL)

April 2, 2026 updated by: University Hospital, Limoges

Cases of encephalitis of varying severity have been described in recent years in eastern France involving tick-borne encephalitis virus (TBEV). The main objective is to demonstrate the presence of TBEV in Limousin, in patients with a positive Lyme serology, or a neurological picture compatible with TBEV.

Study Overview

Status

Completed

Conditions

Tick-borne Encephalitis

Intervention / Treatment

Diagnostic test: anti-TBEV serology

Detailed Description

Cases of encephalitis of varying severity have been described in recent years in eastern France involving tick-borne encephalitis virus (TBEV). The epidemiological situation in France is poorly known with about 20 cases diagnosed per year, mainly in Alsace and Haute-Savoie. The infection can result in fever and an influenza-like picture, which can be complicated by encephalitis-like neurological disorders, or even death. TBEV is transmitted by the tick Ixodes ricinus, which also carries Borrelia burgdorferi, the agent of Lyme disease. Limousin is one of the French regions with the highest prevalence of Lyme disease. These ticks can harbor various pathogens, including TBEV. A case was described in 2007 in Bordeaux. More recently, a case was described in Haute-Loire. The investigators are therefore interested today in the emergence of this virus in Limousin following a possible progression through the Massif Central, potentially favored by numerous anti-Covid-19 control containments. The study begins with a computer extraction of patients with Lyme serology from our GLIMS laboratory software (with positive or negative results), a check for non-oppositions. Then the investigators will measure by ELISA in microplates the anti-TBEV IgG as well as the anti-TBEV IgM on the sera + in TBEV IgG. The investigators will then send a patient questionnaire with an information note to document the context of this TBEV seropositivity and to eliminate false-positivities (vaccination). Finally, the investigators will perform PCR on CSF if serum positive and CSF available, followed by an analysis of results.

Study Type

Observational

Enrollment (Actual)

878

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

France
- - Limoges, France, 87000
    - Limoges University Hosiptal

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

Child
Adult
Older Adult

Accepts Healthy Volunteers

N/A

Sampling Method

Non-Probability Sample

Study Population

patients with Lyme serology from our GLIMS laboratory software (with positive or negative results)

Description

Inclusion Criteria:

Patient with Lyme serology. Neurological picture compatible with neuroborreliosis or encephalitis.
No objection from the patient to the use of biobank samples

Exclusion Criteria:

Patient's opposition.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Detection of anti-TBEV antibodies in serum Time Frame: month 1	The primary endpoint is the detection of anti-TBEV antibodies in the serum of the study population.	month 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Search for the presence of TBEV in the CSF in case of positive serology. Determine the risk factors associated with this infection. Time Frame: month 2	the detection of TBEV RNA will be carried out by real-time RT-PCR in the CSF of patients with positive anti-TBEV serology (if associated CSF available). The analysis will be qualitative in order to obtain a positive/negative response on the presence of virus RNA in the sample. In order to obtain information on the context of the infection, a questionnaire will be sent to TBEV-positive patients.	month 2

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University Hospital, Limoges

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Bisserier E, Perraud A, Ayhan N, Durand GA, de Lamballerie X, Hantz S. Serological evidence of tick-borne encephalitis virus in limousin, france. Int J Infect Dis. 2026 Apr;165:108424. doi: 10.1016/j.ijid.2026.108424. Epub 2026 Jan 27.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

July 17, 2023

Primary Completion (Actual)

August 13, 2023

Study Completion (Actual)

August 13, 2023

Study Registration Dates

First Submitted

July 4, 2023

First Submitted That Met QC Criteria