Toscana virus (TOSV) (Bunyavirales, Phenuiviridae, Phlebovirus, Toscana phlebovirus) and other related human pathogenic arboviruses are transmitted by phlebotomine sand flies. TOSV has been reported in nations bordering the Mediterranean Sea among other regions. Infection can result in febrile illness as well as meningitis and encephalitis. Understanding vector-arbovirus interactions is crucial to improving our knowledge of how arboviruses spread, and in this context, immune responses that control viral replication play a significant role. Extensive research has been conducted on mosquito vector immunity against arboviruses, with RNA interference (RNAi) and specifically the exogenous siRNA (exo-siRNA) pathway playing a critical role. However, the antiviral immunity of phlebotomine sand flies is less well understood. Here we were able to show that the exo-siRNA pathway is active in a Phlebotomus papatasi-derived cell line. Following TOSV infection, distinctive 21 nucleotide virus-derived small interfering RNAs (vsiRNAs) were detected. We also identified the exo-siRNA effector Ago2 in this cell line, and silencing its expression rendered the exo-siRNA pathway largely inactive. Thus, our data show that this pathway is active as an antiviral response against a sand fly transmitted bunyavirus, TOSV.
- MeSH
- arboviry * genetika MeSH
- lidé MeSH
- malá interferující RNA genetika MeSH
- Phlebotomus * genetika MeSH
- Phlebovirus * genetika MeSH
- Psychodidae * genetika MeSH
- RNA interference MeSH
- virus horečky pappataci * genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Recently, Balkan virus (BALKV, family Phenuiviridae, genus Phlebovirus) was discovered in sand flies collected in Albania and genetically characterised as a member of the Sandfly fever Naples species complex. To gain knowledge concerning the geographical area where exposure to BALKV exists, entomological surveys were conducted in 2014 and 2015, in Croatia, Bosnia and Herzegovina (BH), Kosovo, Republic of Macedonia and Serbia. RESULTS: A total of 2830 sand flies were trapped during 2014 and 2015 campaigns, and organised as 263 pools. BALKV RNA was detected in four pools from Croatia and in one pool from BH. Phylogenetic relationships were examined using sequences in the S and L RNA segments. Study of the diversity between BALKV sequences from Albania, Croatia and BH showed that Albanian sequences were the most divergent (9-11% [NP]) from the others and that Croatian and BH sequences were grouped (0.9-5.4% [NP]; 0.7-5% [L]). The sand fly infection rate of BALKV was 0.26% in BH and 0.27% in Croatia. Identification of the species content of pools using cox1 and cytb partial regions showed that the five BALKV positive pools contained Phlebotomus neglectus DNA; in four pools, P neglectus was the unique species, whereas P. tobbi DNA was also detected in one pool. CONCLUSIONS: We report here (i) the first direct evidence that the Balkan virus initially described in coastal Albania has a much wider dissemination area than originally believed, (ii) two real-time RT-PCR assays that may be useful for further screening of patients presenting with fever of unknown origin that may be caused by Balkan virus infection, (iii) entomological results suggesting that Balkan virus is likely transmitted by Phlebotomus neglectus, and possibly other sand fly species of the subgenus Larroussius. So far, BALKV has been detected only in sand flies. Whether BALKV can cause disease in humans is unknown and remains to be investigated.
- MeSH
- entomologie metody MeSH
- fylogeneze MeSH
- hmyz - vektory virologie MeSH
- horečka neznámého původu diagnóza epidemiologie virologie MeSH
- horečka pappataci epidemiologie přenos virologie MeSH
- kvantitativní polymerázová řetězová reakce MeSH
- lidé MeSH
- Psychodidae virologie MeSH
- RNA virová genetika MeSH
- virus horečky pappataci genetika fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Albánie epidemiologie MeSH
- Balkánský poloostrov epidemiologie MeSH
- Bosna a Hercegovina epidemiologie MeSH
- Chorvatsko epidemiologie MeSH
- Srbsko epidemiologie MeSH
Sandfly-borne phleboviruses are endemic in the Mediterranean basin. However, levels of exposure of human and animal populations are inadequately researched. Toscana virus (TOSV) is present in Portugal where it causes human infection and disease; in contrast there are few data for sandfly fever Sicilian virus (SFSV) which has neither been isolated nor detected by molecular tests and for which there are only limited serological data. The sera collected from 1160 dogs and 189 cats in southern Portugal were tested for the presence of neutralizing antibodies against TOSV and SFSV, two viruses recognized as distinct serocomplexes in the Mediterranean region. Our data showed (i) seropositivity to TOSV and SFSV in dogs at a rate of 6.8 and 50.8 %, respectively, and (ii) that 3.7 % of cats were seropositive for TOSV. TOSV findings are in line with previous results obtained with less stringent serological assays. Our results for SFSV in dogs clearly indicate that the virus is circulating widely and that humans may be exposed to infection via the dogs. Although the presence of SFSV was suggested by haemagglutination inhibition in 4/1690 human sera in 1974, this is the first time, as far as we know, that SFSV has been shown to circulate so widely in dogs in Portugal. Future studies should be directed at isolating strains of SFSV in Portugal from dogs, humans and sandflies collected in high prevalence regions. As dogs appear to be good sentinels for SFSV, their role as a possible reservoir in the natural cycle should also be considered.
- MeSH
- horečka pappataci krev veterinární virologie MeSH
- kočky MeSH
- nemoci koček krev virologie MeSH
- nemoci psů krev virologie MeSH
- neutralizující protilátky krev MeSH
- Phlebovirus imunologie izolace a purifikace MeSH
- protilátky virové krev MeSH
- psi MeSH
- séroepidemiologické studie MeSH
- virus horečky pappataci imunologie izolace a purifikace MeSH
- zvířata MeSH
- Check Tag
- kočky MeSH
- mužské pohlaví MeSH
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Portugalsko epidemiologie MeSH
Článek podává přehled transmisivních onemocnění, která byla evidována v celostátním hlásícím programu EPIDAT v letech 2004–2013. Nejčastějšími vektorem přenášenými chorobami v ČR jsou lymeská borrelióza a klíšťová encefalitida. Nejčastěji importovanými nemocemi jsou horečka dengue a malárie. Význam transmisivních nákaz stoupá se změnami klimatu a narůstající oblibou cest do exotických zemí.
A review is presented of transmissible diseases reported to the national EPIDAT system in 2004-2013. The most frequent vector-borne diseases in the Czech Republic are Lyme borreliosis and tick-borne encephalitis. The most frequently imported diseases are dengue fever and malaria. Transmissible infections become of increasing concern with climate change and surge of interest in travel to exotic countries.
- MeSH
- babezióza epidemiologie přenos MeSH
- ehrlichióza epidemiologie farmakoterapie přenos MeSH
- hemoragická horečka dengue epidemiologie přenos MeSH
- hlášení nemocí MeSH
- infekce bakteriemi rodu Bartonella epidemiologie přenos MeSH
- infekce přenášené vektorem * MeSH
- infekční nemoci * epidemiologie přenos MeSH
- klíšťová encefalitida epidemiologie MeSH
- leishmanióza epidemiologie přenos MeSH
- lidé MeSH
- lymeská nemoc epidemiologie přenos MeSH
- malárie epidemiologie přenos MeSH
- Q-horečka epidemiologie přenos MeSH
- tularemie epidemiologie farmakoterapie přenos MeSH
- věkové rozložení MeSH
- virus chikungunya izolace a purifikace patogenita účinky léků MeSH
- virus horečky pappataci izolace a purifikace patogenita růst a vývoj MeSH
- viry kalifornské encefalitidy izolace a purifikace patogenita účinky léků MeSH
- západonilská horečka epidemiologie přenos MeSH
- Check Tag
- lidé MeSH
Autoři referují kazuistiky 3 pacientů s aseptickou meningoencefalitidou, která se rozvinula po návratu ze středomořských turistických destinací. U pacientů nebyl zjištěn žádný z původců aseptických neuroinfekcí běžných v ČR. Následné sérologické vyšetření prokázalo, že onemocnění bylo způsobeno virem Toscana, flebovirem z čeledi Bunyaviridae. Jedná se o virus přenášený drobným bodavým hmyzem rodu Phlebotomus, který se hojně vyskytuje v oblasti Středozemního moře. Průběh onemocnění u všech pacientů byl lehký až středně těžký, všichni se uzdravili bez následků. Uvedené kazuistiky dokumentují skutečnost, že tento nepříliš známý arbovirus patří do diferenciálně diagnostické rozvahy u pacientů s aseptickou neuroinfekcí po návratu z oblastí výskytu tohoto viru.
Presented are case studies of 3 patients with aseptic meninogencephalitis occurring after returning from the Mediterranean tourist regions. None of the infectious agents common in aseptic neuroinfections in the Czech Republic was detected in the patients. Serological tests showed that in each case, the illness was caused by Toscana virus, a phlebovirus belonging to the family Bunyaviridae. The virus is transmitted by tiny biting insects of the genus Phlebotomus commonly present in the Mediterranean area. The course of the disease was mild to moderate and all the patients recovered without sequelae. These case reports document the fact that this arbovirus should be considered in the differential diagnosis of patients with aseptic neuroinfections returning from endemic areas of this virus.
- MeSH
- Bunyaviridae patogenita MeSH
- cestování MeSH
- diferenciální diagnóza MeSH
- dospělí MeSH
- importované infekce MeSH
- lidé středního věku MeSH
- lidé MeSH
- meningitida aseptická * diagnóza etiologie farmakoterapie krev terapie virologie MeSH
- meningoencefalitida * diagnóza etiologie farmakoterapie terapie virologie MeSH
- Phlebovirus patogenita MeSH
- sérologické testy MeSH
- virus horečky pappataci * patogenita MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
- MeSH
- japonská encefalitida MeSH
- lidé MeSH
- lidský herpesvirus 6 MeSH
- nemoci nervového systému MeSH
- poliomyelitida MeSH
- pravé neštovice MeSH
- přenos infekční nemoci MeSH
- progresivní multifokální leukoencefalopatie MeSH
- rabies MeSH
- virus Hendra MeSH
- virus horečky pappataci MeSH
- virus Nipah MeSH
- západonilská horečka epidemiologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
