PERSISTENCE MORE THEN 2 MONTH OF TICK-BORNE ENCEPHALITIS VIRUS IN CENTRAL NERVOUS SYSTEM AND LYMPHOID ORGANS OF MICE AFTER IMMUNIZATION WITH LOW DOSES OF LANGAT/DENGUE4 CHIMERA FOLLOWED BY INFECTION WITH HIGH VIRULENCE TICK-BORNE ENCEPHALITIS VIRUS

Flaviviruses are major emerging human pathogens on a global scale. Some flaviviruses can infect the central nervous system of the host and therefore are regarded as neurotropic. The most clinically relevant classical neurotropic flaviviruses include Japanese encephalitis virus, West Nile virus, and tick-borne encephalitis virus. In this review, we focus on these flaviviruses and revisit the concepts of flaviviral neurotropism, neuropathogenicity, neuroinvasion, and resultant neuropathogenesis. We attempt to synthesize the current knowledge about interactions between the central nervous system and flaviviruses from the neuroanatomical and neuropathological perspectives and address some misconceptions and controversies. We hope that revisiting these neuropathological concepts will improve the understanding of flaviviral neuroinfections. This, in turn, may provide further guiding foundations for relevant studies of other emerging or geographically expanding flaviviruses with neuropathogenic potential, such as Zika virus and dengue virus, and pave the way for intelligent therapeutic strategies harnessing potentially beneficial, protective host responses to interfere with disease progression and outcome.

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Basis of long-term perspective of prophylaxis and treatmentof tick-borne encephalitis

Bulletin of Siberian Medicine ◽

10.20538/1682-0363-2008-1-124-129 ◽

2008 ◽

Vol 7 (1) ◽

pp. 124-129

Author(s):

N. P. Tolokonskaya ◽

E. A. Spiridonov ◽

Yu. V. Kazakova ◽

V. V. Provorov ◽

Ye. V. Druzhinina

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Disease Resistance ◽

Natural Population ◽

Human Disease ◽

Mutual Adaptation ◽

Tick Borne Encephalitis ◽

Population Interactions ◽

Tick Borne Encephalitis Virus

A reflection of natural population interactions between tick-borne encephalitis virus and a human being on condition of mutual adaptation appears to be a frequent persistence of an agent and a high human disease resistance. Mixed somatic pathology of degenerative nature, which was revealed in the study of the majority of patients with tick-borne encephalitis, more often including the initial central nervous system affliction under conditions of negative changes of organism reactivity, is regarded as one of the main reasons of infection conversion into disease. The virus becomes an aggression factor at such joint biological causes, changing endobiocenosis, which is of great importance for substantiation of curing therapy.

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Climate, ticks and tick-borne encephalitis in Central Europe.

10.1079/9781789249637.0047 ◽

2021 ◽

pp. 331-340

Author(s):

Vlasta Danielová ◽

Milan Daniel

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Central Europe ◽

Human Disease ◽

European Area ◽

Tick Borne Encephalitis ◽

The Family ◽

The Central Nervous System ◽

Tick Borne Encephalitis Virus ◽

European Subtype

Abstract Tick-borne encephalitis (TBE) is a serious human disease of the central nervous system (CNS) caused by the European subtype of tick-borne encephalitis virus (TBEV) - genus Flavivirus of the family Flaviviridae - in the European area of its distribution. Its major vector is the tick, Ixodes ricinus. This expert opinion discusses the ecology of I. ricinus and the epidemiology of TBE in relation to changing climate in Central Europe.

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Assessment of the YKL-40 concentration in patients with tick-borne encephalitis

10.21203/rs.3.rs-135104/v1 ◽

2020 ◽

Author(s):

Piotr Czupryna ◽

Agnieszka Kulczyńka-Przybik ◽

Barbara Mroczko ◽

Mulugeta Wondim ◽

Sambor Grygorczuk ◽

...

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Early Stage ◽

Central Nervous System Involvement ◽

Control Group ◽

Roc Curve Analysis ◽

Group I ◽

Tick Borne Encephalitis ◽

The Central Nervous System ◽

Tick Borne Encephalitis Virus

Abstract Background Tick-Borne Encephalitis (TBE) is a viral infection of the Central Nervous System (CNS) caused by Tick-Borne Encephalitis Virus (TBEV). It might take several clinical courses such as: meningitis, meningoencephalitis or meningoencephalomyelitis. The aim this study was to compare the YKL-40 concentration in cerebrospinal fluid (CSF) of patients with different clinical presentations of TBE and patients with excluded meningitis (control group). Methods The concentration of YKL-40 in CSF was determined using Fujirebio tests (Ghent, Belgium) in 32 patients with TBE: group I—patients with meningoencephalitis (n = 16); group II—patients with meningitis (n = 16). The control group (CG) consisted of 17 patients in whom inflammatory process in central nervous system was excluded. Results The concentration of YKL-40 was significantly higher in encephalitis group than in CG after 7 days from the last dose of treatment. The concentration in patients with neuroinflammation had significantly different concentration of YKL-40 compared to patients with no neuroinflammation control groups. ROC curve analysis indicates that: CSF YKL-40 concentration at cut off 783.87 differentiated TBE patients from CG with 100% specificity and 70% sensitivity and CSF YKL-40 concentration at cut off 980.11 differentiated meningitis from meningoencephalitis with 87.5% specificity and 62.5% sensitivity. Conclusions YKL-40 takes part in TBE pathogenesis, its concentration is the highest at the early stage of Central Nervous System involvement and decreases in the convalescent period. As YKL-40 is significantly higher in meningitis than in meningoencephalitis, it might be used as biomarker in differentiation of these clinical forms of TBE.

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Tick-borne encephalitis virus isolates from natural foci of the Irkutsk region: clarification of the genotype landscape

Voprosy Virusologii ◽

10.18821/0507-4088-2016-61-5-229-234 ◽

2016 ◽

Vol 61 (5) ◽

pp. 229-234 ◽

Cited By ~ 1

Author(s):

O. V. Mel’Nikova ◽

R. V. Adel’Shin ◽

V. M. Korzun ◽

Yu. N. Trushina ◽

E. I. Andaev

Keyword(s):

Small Mammals ◽

Encephalitis Virus ◽

Ixodes Persulcatus ◽

Tick Borne Encephalitis ◽

Irkutsk Region ◽

High Virulence ◽

Natural Foci ◽

Tick Borne Encephalitis Virus ◽

Relationship Of ◽

Far Eastern

The Irkutsk region is the unique territory where all known subtypes of tick-borne encephalitis virus (TBEV) circulate. In the last years, the phenomenon of changes in TBEV subtypes (substitution of the Far-Eastern subtype by the Siberian one) was noted in some regions of the Russian Federation. The results of individual investigation of 11522 Ixodes persulcatus ticks and brain specimens from 81 small mammals collected in natural foci of the Irkutsk region during 2006-2014 are presented in the article. More than 60 TBEV strains have been isolated and studied by virological methods; E gene fragments (1193 b.p.) of 68 isolates have been typed. The majority of the strains (irrespective of subtype) were of high virulence for laboratory mice (LM) in case of both intracerebral and subcutaneous inoculation of virus. All isolates from warm-blooded small mammals and humans were of high virulence for LM, but placed in the same clusters of the phylogenetic tree with ticks collected in the same area. Tick-borne strains of different virulence also did not form separate clusters on the tree. Phylogenetic analysis showed that modern TBEV genotypic landscape of the studied territory is changing toward absolute predominance of the Siberian subtype (94.1%). This subtype is represented by two groups with prototype strains “Zausaev” and “Vasilchenko”. The “Vasilchenko” group of strains is spread on the whole territory under study; the strains of “Zausaev” group were isolated previously in the Irkutsk suburbs. The European subtype of TBEV circulates in natural foci of Pribaikalie permanently (at least 5% of the random sampling); the strains are of high virulence for LM. The Far-Eastern TBEV subtype was not found within the group of isolates collected in 20062014. The phylogenetic relationship of the strains under study had a higher correlation with the place of isolation than with the year or source.

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