Categorization systems for tick-borne encephalitis virus (TBEV) infection lack consistency in classifying disease severity. To evaluate the need for a standard, consensus-based categorisation system for TBEV infection across subtypes, we gathered an expert panel of clinicians and scientists with diverse expertise in TBEV infection. Consensus was sought using the Delphi technique, which consisted of 2 web-based survey questionnaires and a final, virtual, consensus-building exercise. Ten panellists representing 8 European countries participated in the Delphi exercise, with specialities in neurology, infectious disease, paediatrics, immunology, virology, and epidemiology. Panellists reached unanimous consensus on the need for a standardised, international categorisation system to capture both clinical presentation and severity of TBEV infection. Ideally, such a system should be feasible for use at bedside, be clear and easy to understand, and capture both the acute and follow-up phases of TBEV infection. Areas requiring further discussion were (1) the timepoints at which assessments should be made and (2) whether there should be a separate system for children. This Delphi panel study found that a critical gap persists in the absence of a feasible and practical classification system for TBEV infection. Specifically, the findings of our Delphi exercise highlight the need for the development of a user-friendly classification system that captures the acute and follow-up (i.e., outcome) phases of TBEV infection and optimally reflects both clinical presentation and severity. Development of a clinical categorisation system will enhance patient care and foster comparability among studies, thereby supporting treatment development, refining vaccine strategies, and fortifying public health surveillance.
- MeSH
- Delphi Technique * MeSH
- Encephalitis, Tick-Borne * epidemiology virology diagnosis MeSH
- Consensus MeSH
- Humans MeSH
- Encephalitis Viruses, Tick-Borne * classification MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Kliešťová encefalitída (KE) je opomínaná neuroinvazívna antropozoonóza. Väčšina prípadov KE má mierny priebeh, ale u niektorých pacientov s encefalitídou sa vyvinú dlhodobé neurologické alebo neuropsychické následky. Uvádzame fatálny prípad KE z endemickej oblasti. Prípad sa vyskytol u muža v strednom veku bez epidemiologických dôkazov o uhryznutí kliešťom alebo konzumácii surových mliečnych výrobkov a ktorý nebol očkovaný proti KE. Cieľom tohto príspevku je upozorniť na potrebu lepšej znalosti rizikových faktorov spojených s kliešťovou encefalitídou s dlhodobými následkami, zlepšiť manažment prípadov a podnietiť vývoj nových vakcinačných stratégií. Podľa našich vedomostí ide o prvý hlásený prípad zriedkavej fatálnej KE u muža stredného veku bez závažných komorbidít na Slovensku.
Tick-borne encephalitis (TBE) is a neglected zoonotic neuroinvasive disease. Most cases of TBE have a mild course, but some patients with encephalitis develop long-term neurological or neuropsychic sequelae. We report a fatal case of TBE in a patient living in an endemic area. The case occurred in a middle-aged man with no epidemiological evidence of tick bites, no consumption of raw dairy products, and who was not vaccinated against TBE. The aim of this paper is to draw attention to the need for better information of the risk factors associated with TBE with the long-term sequelae, to improve case management and to stimulate the development of new vaccination strategies. To our knowledge, this is the first reported case of rare fatal TBE in a middle-aged man with no severe comorbidities in Slovakia.
- MeSH
- Disease Outbreaks statistics & numerical data MeSH
- Fatal Outcome MeSH
- Encephalitis, Tick-Borne * mortality MeSH
- Comorbidity MeSH
- Middle Aged MeSH
- Drug-Related Side Effects and Adverse Reactions MeSH
- Zoonoses epidemiology MeSH
- Check Tag
- Middle Aged MeSH
- Male MeSH
- Publication type
- Case Reports MeSH
- Geographicals
- Slovakia MeSH
BACKGROUND: Tick-borne encephalitis virus (TBEV) is a significant threat to human health. The virus causes potentially fatal disease of the central nervous system (CNS), for which no treatments are available. TBEV infected individuals display a wide spectrum of neuronal disease, the determinants of which are undefined. Changes to host metabolism and virus-induced immunity have been postulated to contribute to the neuronal damage observed in infected individuals. In this study, we evaluated the cytokine, chemokine, and metabolic alterations in the cerebrospinal fluid (CSF) of symptomatic patients infected with TBEV presenting with meningitis or encephalitis. Our aim was to investigate the host immune and metabolic responses associated with specific TBEV infectious outcomes. METHODS: CSF samples of patients with meningitis (n = 27) or encephalitis (n = 25) were obtained upon consent from individuals hospitalised with confirmed TBEV infection in Brno. CSF from uninfected control patients was also collected for comparison (n = 12). A multiplex bead-based system was used to measure the levels of pro-inflammatory cytokines and chemokines. Untargeted metabolomics followed by bioinformatics and integrative omics were used to profile the levels of metabolites in the CSF. Human motor neurons (hMNs) were differentiated from induced pluripotent stem cells (iPSCs) and infected with the highly pathogenic TBEV-Hypr strain to profile the role(s) of identified metabolites during the virus lifecycle. Virus infection was quantified via plaque assay. RESULTS: Significant differences in proinflammatory cytokines (IFN-α2, TSLP, IL-1α, IL-1β, GM-CSF, IL-12p40, IL-15, and IL-18) and chemokines (IL-8, CCL20, and CXCL11) were detected between neurological-TBEV and control patients. A total of 32 CSF metabolites differed in TBE patients with meningitis and encephalitis. CSF S-Adenosylmethionine (SAM), Fructose 1,6-bisphosphate (FBP1) and Phosphoenolpyruvic acid (PEP) levels were 2.4-fold (range ≥ 2.3-≥3.2) higher in encephalitis patients compared to the meningitis group. CSF urocanic acid levels were significantly lower in patients with encephalitis compared to those with meningitis (p = 0.012209). Follow-up analyses showed fluctuations in the levels of O-phosphoethanolamine, succinic acid, and L-proline in the encephalitis group, and pyruvic acid in the meningitis group. TBEV-infection of hMNs increased the production of SAM, FBP1 and PEP in a time-dependent manner. Depletion of the metabolites with characterised pharmacological inhibitors led to a concentration-dependent attenuation of virus growth, validating the identified changes as key mediators of TBEV infection. CONCLUSIONS: Our findings reveal that the neurological disease outcome of TBEV infection is associated with specific and dynamic metabolic signatures in the cerebrospinal fluid. We describe a new in vitro model for in-depth studies of TBEV-induced neuropathogenesis, in which the depletion of identified metabolites limits virus infection. Collectively, this reveals new biomarkers that can differentiate and predict TBEV-associated neurological disease. Additionally, we have identified novel therapeutic targets with the potential to significantly improve patient outcomes and deepen our understanding of TBEV pathogenesis.
- MeSH
- Cytokines cerebrospinal fluid MeSH
- Adult MeSH
- Encephalitis, Tick-Borne * cerebrospinal fluid metabolism MeSH
- Cells, Cultured MeSH
- Middle Aged MeSH
- Humans MeSH
- Metabolome * physiology MeSH
- Metabolomics MeSH
- Young Adult MeSH
- Neurons * metabolism virology MeSH
- Aged MeSH
- Encephalitis Viruses, Tick-Borne * MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Young Adult MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Keywords
- postencefalitický syndrom,
- MeSH
- Encephalitis, Tick-Borne * epidemiology complications prevention & control MeSH
- Humans MeSH
- Paresis MeSH
- Vaccination MeSH
- Check Tag
- Humans MeSH
UNLABELLED: We investigated the tripartite interactions between two intracellular bacterial symbionts, Cardinium and Wolbachia in Tyrophagus putrescentiae. Cultures of Tyrophagus putrescentiae are typically single-infected by one intracellular symbiont. However, co-infection can be experimentally induced by mixing single-infected cultures, resulting in 10% of mite individuals being double-infected (Cardinium + Wolbachia) and a corresponding reduction in host fitness. Here, we assembled the genomes of Cardinium and Wolbachia and analyzed their gene expression in parental single-infected and mixed mite cultures using population-level samples (ranging from 7,500 to 10,000 mites). Wolbachia interacts more extensively with its mite host than Cardinium in single-infected cultures. However, in mixed cultures, (i) Wolbachia exhibited reduced regulation of the host compared with Cardinium; (ii) the gene expression profile of Cardinium shifted, increasing its interactions with the host, whereas the gene expression profile of Wolbachia remained unchanged; and (iii) Wolbachia genes exhibited a loss of interactions with mite gene expression, as indicated by reduced correlations (for example with host MAPK, endocytosis, and calcium signaling pathways). The experiments show that at the mite population level, symbiont infection disrupts gene expression interaction between the two symbionts and their host in different ways. Wolbachia was more influenced by Cardinium gene expression than vice versa. Cardinium can inhibit the growth of Wolbachia by disrupting its interaction with the host, leading to a loss of Wolbachia's influence on mite immune and regulatory pathways. The reasons for responses are due to co-infection or the reduced frequency of Wolbachia single-infected individuals due to the analyses of population-level samples. IMPORTANCE: We found that Cardinium disrupts the interaction between Wolbachia and mite host. In Wolbachia single-infected cultures, strong correlations exist between symbiont and host gene expressions. Interestingly, although Cardinium can also interact with the host, this interaction appears weaker compared with Wolbachia in single-infected cultures. These results suggest that both symbionts affect mite host gene expression, particularly in immune and regulatory pathways. In mixed samples, Cardinium appears to outcompete Wolbachia by disrupting its host interaction. It indicates competition between these two intracellular symbionts in mite populations. Wolbachia belongs to a mite-specific supergroup Q, distinct from the more commonly studied Wolbachia supergroups. As these mite-specific bacteria exhibit pathogen-blocking effects, our findings may have relevance for other systems, such as ticks and tick-borne diseases. The study sheds light on intracellular symbiont interaction within a novel mite-symbiont model.
- MeSH
- Bacteroidetes * physiology genetics MeSH
- Mites * microbiology MeSH
- Symbiosis MeSH
- Wolbachia * genetics physiology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
OBJECTIVES: The aim of the study was to evaluate the efficiency of molecular diagnostics of tick-borne encephalitis (TBE) and to correlate viral RNA (vRNA) detection with the clinical and laboratory data. METHODS: Clinical samples from 1125 patients from South Bohemia, Czech Republic, a highly endemic TBE region, were screened for TBE virus (TBEV) RNA by RT-qPCR. Samples included blood, serum, cerebrospinal fluid (CSF), and urine. RESULTS: TBEV RNA was detected in 14 patients with clinically proven TBE. TBEV RNA was most frequently detected in sera during early infection (11/37 patients tested, 29.7%) but decreased with rising IgG antibody response (3/228, 1.3%). Detection in CSF and urine was infrequent (1/30, 3.3% and 1/52, 1.9%, respectively). Additionally, five patients initially not diagnosed with TBE were retrospectively found to have TBEV RNA in serum, indicating possible underdiagnosis, particularly in mild or atypical presentations. The study also highlighted the diagnostic challenge of an immunocompromised patient whose delayed antibody response hindered timely diagnosis. In such cases, RT-qPCR could significantly shorten the diagnostic timeline. CONCLUSIONS: These findings underscore the value of early RNA detection in improving the diagnosis of TBE and may in the future facilitate the early administration of potential treatment, thereby improving patient outcomes.
- MeSH
- Molecular Diagnostic Techniques methods MeSH
- Child MeSH
- Adult MeSH
- Immunoglobulin G blood MeSH
- Encephalitis, Tick-Borne * diagnosis virology MeSH
- Real-Time Polymerase Chain Reaction MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Young Adult MeSH
- Child, Preschool MeSH
- Antibodies, Viral blood MeSH
- RNA, Viral * blood cerebrospinal fluid isolation & purification MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Encephalitis Viruses, Tick-Borne * isolation & purification genetics MeSH
- Check Tag
- Child MeSH
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Young Adult MeSH
- Male MeSH
- Child, Preschool MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
Tick-borne encephalitis virus (TBEV) infection can manifest as disease of variable severity, ranging from subclinical infection to severe disease with neurological involvement and potentially fatal outcome. Although TBE is recognized as a major public health problem in Europe, the true burden of disease is potentially underestimated. Here, we investigated TBEV-specific antibody prevalence, infection incidence, and seroreversion and antibody decline rates in a prospective Swiss healthcare worker (HCW) cohort. We screened serum samples from 1444 HCWs between June and October 2020, and from a subset again between August and September 2021, using a TBEV envelope (E) protein IgG ELISA. Positive samples underwent further analysis with a TBEV non-structural protein 1 (NS1) IgG ELISA, and seroconversions in unvaccinated individuals were confirmed by seroneutralization testing. Questionnaire data were used to determine vaccination status and risk factors. TBEV E protein-specific IgG prevalence was 72.1% (95% CI 68.2-75.7%) in TBEV-vaccinated and 6% (95% CI 4.4-7.8%) in unvaccinated individuals. The estimated annual incidence of infection was 735/100,000. Age was the only factor significantly associated with seroprevalence. The seroreversion rate in unvaccinated individuals was 30.3% within one year, which is almost ten times higher than in vaccinated individuals (3.4%, annual decline rate 8.0%). NS1-specific IgG antibodies were six times more common in vaccinated than unvaccinated HCWs. In conclusion, undetected TBEV infections are common, and infection incidence is much higher than reported clinical cases. Individuals with abortive infections have high antibody decline and seroreversion rates. Whether lifelong protection is conferred and by which immune subsets remain unclear.
- MeSH
- Adult MeSH
- Immunoglobulin G blood MeSH
- Incidence MeSH
- Encephalitis, Tick-Borne * epidemiology immunology blood MeSH
- Middle Aged MeSH
- Humans MeSH
- Prospective Studies MeSH
- Antibodies, Viral * blood MeSH
- Aged MeSH
- Seroepidemiologic Studies MeSH
- Encephalitis Viruses, Tick-Borne * immunology MeSH
- Health Personnel statistics & numerical data MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Switzerland MeSH
Ticks are important vectors of various microorganisms, including bacteria. In this study, we examined Hyalomma aegyptium ticks collected from 240 spur-thighed tortoises Testudo graeca at 42 localities in the Mediterranean and Middle East and analysed them for the presence of bacteria of the genera Anaplasma, Borrelia, Coxiella, and Rickettsia. Altogether, 576 out of 928 analysed ticks (62.1%) were positive for at least one of the tested bacteria. The highest prevalence in individual ticks was found for Borrelia turcica (43.6%), followed by Rickettsia (12.3%) and Anaplasma (6.1%). No sample was positive for Coxiella burnetii. Among Rickettsia, we detected two species, Rickettsia africae and Rickettsia aeschlimannii, and also other unspecified Rickettsia. Anaplasma (100% identity with A. phagocytophilum) was detected at 15 (35%) out of 42 studied localities, any of Rickettsia at 28 (67%), and B. turcica at 32 (76%) localities. The geographic distribution of the studied microorganisms varied, with none of them detected in Syria, and only Rickettsia spp. detected in Morocco. Sequence analysis revealed substantial genetic variability in all detected agents, with the most variable (36 new haplotypes) being glpQ gene used as a marker for B. turcica. We also analysed the prevalence of various co-infections among studied ticks, with the mean number of co-infected ticks per tortoise increased with the number of ticks per tortoise. However, the frequencies of co-infected ticks do not indicate the presence of antagonistic or synergistic facilitative interactions between the agents. According to our data, we could expect that the eco-epidemiological importance of H. aegyptium does not stem from their tortoise hosts but rather from the low host specificity of its larvae and nymphs, feeding on a wider spectrum of reptilian, avian, and mammalian hosts.
- MeSH
- Anaplasma * isolation & purification MeSH
- Borrelia isolation & purification MeSH
- Coxiella isolation & purification genetics MeSH
- Tick Infestations veterinary epidemiology parasitology MeSH
- Ixodidae * microbiology growth & development MeSH
- Rickettsia * isolation & purification MeSH
- Turtles * microbiology MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Middle East MeSH
- Mediterranean Region MeSH
