| isolation of a new flavivirus related to cell fusing agent virus (cfav) from field-collected flood-water aedes mosquitoes sampled from a dambo in central kenya. | cell fusing agent virus (cfav) is an rna insect virus that was isolated from a line of aedes aegypti mosquito cells and has been assigned to the family flaviviridae, genus flavivirus. we report here the first isolation of a cfa-like virus from field-collected mosquitoes. mosquito larvae and pupae were sampled from flooded dambos in central province, kenya during the short rain season of 1999. specimens were reared to adults, identified and pooled by species and were tested for the presence of vi ... | 2003 | 12756616 |
| genetic and phenotypic characterization of the newly described insect flavivirus, kamiti river virus. | we have described in the accompanying paper by sang, et al., ([57], arch virol 2003, in press) the isolation and identification of a new flavivirus, kamiti river virus (krv), from ae. macintoshi mosquitoes that were collected as larvae and pupae from flooded dambos in central province, kenya. among known flaviviruses, krv was shown to be most similar to, but genetically and phenotypically distinct from, cell fusing agent virus (cfav). krv was provisionally identified as an insect-only flavivirus ... | 2003 | 12756617 |
| sequences of flavivirus-related rna viruses persist in dna form integrated in the genome of aedes spp. mosquitoes. | flavivirus-related sequences have been discovered in the dsdna genome of aedes albopictus and aedes aegypti mosquitoes, demonstrating for the first time an integration into a eukaryotic genome of a multigenic sequence from an rna virus that replicates without a recognized dna intermediate. in the aedes albopictus c6/36 cell line, an open reading frame (orf) of 1557 aa with protease/helicase and polyprotein processing domains characteristic of flaviviruses was identified. it is closely related to ... | 2004 | 15218182 |
| the modeled structure of the rna dependent rna polymerase of gbv-c virus suggests a role for motif e in flaviviridae rna polymerases. | the flaviviridae virus family includes major human and animal pathogens. the rna dependent rna polymerase (rdrp) plays a central role in the replication process, and thus is a validated target for antiviral drugs. despite the increasing structural and enzymatic characterization of viral rdrps, detailed molecular replication mechanisms remain unclear. the hepatitis c virus (hcv) is a major human pathogen difficult to study in cultured cells. the bovine viral diarrhea virus (bvdv) is often used as ... | 2005 | 16225688 |
| isolation of a new strain of the flavivirus cell fusing agent virus in a natural mosquito population from puerto rico. | the genus flavivirus contains approximately 70 single-stranded, positive-sense rna viruses that are mosquito-borne, tick-borne or have no known vector. two discoveries support previous suggestions of the existence of a large number of unsampled flaviviruses: (i) a new flavivirus, kamiti river virus, was recently isolated from kenyan mosquitoes, and (ii) sequences with high similarity to those of flaviviruses have been found integrated into the genome of aedes mosquitoes, suggesting a past infect ... | 2006 | 16528021 |
| the 3' untranslated regions of kamiti river virus and cell fusing agent virus originated by self-duplication. | previously, it was shown that the 3' untranslated region (3'utr) of kamiti river virus (krv) is nearly twice as long as the 3'utr of other flaviviruses (1208 nucleotides compared with 730 nucleotides for the longest 3'utr of any virus in the tick-borne encephalitis virus species). additionally, krv and the closely related cell fusing agent virus (cfav) were shown to contain two short, almost perfect repeat sequences of 67 nucleotides. however, the construction of a robust comparative nucleotide ... | 2006 | 16894200 |
| genetic characterization of a new insect flavivirus isolated from culex pipiens mosquito in japan. | we found a new flavivirus that is widespread in culex pipiens and other culex mosquitoes in japan. the virus isolate, named culex flavivirus (cxfv), multiplied only in mosquito cell lines producing a moderate cytopathic effect, but did not grow in mammalian cells. the cxfv genome is single-stranded rna, 10,834 nt in length and containing a single open reading frame encoding a polyprotein of 3362 aa with 5' and 3' untranslated regions (utrs) of 91 and 657 nt, respectively. phylogenetic analyses r ... | 2007 | 17070886 |
| curation of viral genomes: challenges, applications and the way forward. | whole genome sequence data is a step towards generating the 'parts list' of life to understand the underlying principles of biocomplexity. genome sequencing initiatives of human and model organisms are targeted efforts towards understanding principles of evolution with an application envisaged to improve human health. these efforts culminated in the development of dedicated resources. whereas a large number of viral genomes have been sequenced by groups or individuals with an interest to study a ... | 2006 | 17254296 |
| universal primers that amplify rna from all three flavivirus subgroups. | species within the flavivirus genus pose public health problems around the world. increasing cases of dengue and japanese encephalitis virus in asia, frequent outbreaks of yellow fever virus in africa and south america, and the ongoing spread of west nile virus throughout the americas, show the geographical burden of flavivirus diseases. flavivirus infections are often indistinct from and confused with other febrile illnesses. here we review the specificity of published primers, and describe a n ... | 2008 | 18218114 |
| constancy and diversity in the flavivirus fusion peptide. | flaviviruses include the mosquito-borne dengue, japanese encephalitis, yellow fever and west nile and the tick-borne encephalitis viruses. they are responsible for considerable world-wide morbidity and mortality. viral entry is mediated by a conserved fusion peptide containing 16 amino acids located in domain ii of the envelope protein e. highly orchestrated conformational changes initiated by exposure to acidic ph accompany the fusion process and are important factors limiting amino acid change ... | 2008 | 18275613 |
| detection and monitoring of mosquito flaviviruses in spain between 2001 and 2005. | between the years 2001 and 2005, a total of 72,895 female mosquitoes were trapped during their season of abundance, and analyzed. they were sorted into 4,723 pools belonging to 20 culicidae species from the anopheles, aedes, ochlerotatus, culex, culiseta, coquillettidia, and uranotaenia genera. the aim was to detect arboviral rna directly from mosquito homogenates for the genera alphavirus, flavivirus, and phlebovirus. the study formed part of general arbovirus transmission research in four of t ... | 2009 | 18959502 |
| detection of rna from a novel west nile-like virus and high prevalence of an insect-specific flavivirus in mosquitoes in the yucatan peninsula of mexico. | as part of our ongoing surveillance efforts for west nile virus (wnv) in the yucatan peninsula of mexico, 96,687 mosquitoes collected from january through december 2007 were assayed by virus isolation in mammalian cells. three mosquito pools caused cytopathic effect. two isolates were orthobunyaviruses (cache valley virus and kairi virus) and the identity of the third infectious agent was not determined. a subset of mosquitoes was also tested by reverse transcription-polymerase chain reaction (r ... | 2009 | 19141845 |
| kupe virus, a new virus in the family bunyaviridae, genus nairovirus, kenya. | we have previously described isolation and preliminary identification of a virus related to dugbe virus (dugv), family bunyaviridae, genus nairovirus. six isolates of the virus were obtained from pools of amblyomma gemma and rhipicephalus pulchellus ticks collected from hides of cattle in nairobi, kenya, in october 1999. we report results of further characterization of this virus, including growth kinetics in cell culture and full-length genome sequencing and genetic characterization, which show ... | 2009 | 19193256 |
| a new flavivirus and a new vector: characterization of a novel flavivirus isolated from uranotaenia mosquitoes from a tropical rain forest. | a novel flavivirus was isolated from uranotaenia mashonaensis, a mosquito genus not previously known to harbor flaviviruses. mosquitoes were caught in the primary rain forest of the taï national park, côte d'ivoire. the novel virus, termed nounané virus (nouv), seemed to grow only on c6/36 insect cells and not on vertebrate cells. typical enveloped flavivirus-like particles of 60 to 65 nm in diameter were detected by electron microscopy in the cell culture supernatant of infected cells. the full ... | 2009 | 19224998 |
| flavivirus rna in phlebotomine sandflies. | sandfly-transmitted phleboviruses, such as toscana, sandfly fever sicilian, and sandfly fever naples, can cause human disease and circulate at high rates in mediterranean countries. previous studies have also established that viruses other than phleboviruses may be detected in and isolated from sand flies. the recent detection and isolation (in a large variety of mosquito species) of insect-only flaviviruses related to cell fusing agent virus has indicated that the latter is not an evolutionary ... | 2010 | 19492949 |
| surveillance of mosquito-borne viruses in alberta using reverse transcription polymerase chain reaction with generic primers. | mosquitoes collected during 2003, 2004, and 2005 in alberta, canada, were screened for the presence of a wide range of arboviruses by reverse transcription-polymerase chain reaction (rt-pcr). nucleic acid extracts from mosquito slurries were amplified using universal primers designed to detect viruses belonging to the flavivirus genus of the flaviviridae family and california and bunyamwera serogroups of the bunyavirus genus within the bunyaviridae family. species-specific detection of western e ... | 2009 | 19496438 |
| detection of novel insect flavivirus sequences integrated in aedes albopictus (diptera: culicidae) in northern italy. | the presence of dna sequences integrated from a new flavivirus related to cell fusing agent and kamiti river virus was identified in wild aedes albopictus mosquito populations from the provinces of trentino and padova, northern italy. field work was developed during august-october 2007 with bg-traps, and mosquitoes were screened for flavivirus and alphavirus. no alphavirus was detected, indicating that chikungunya virus is not present in these mosquitoes in trentino and padova area. however, 21% ... | 2009 | 19575816 |
| isolation and characterization of a new insect flavivirus from aedes albopictus and aedes flavopictus mosquitoes in japan. | we isolated a new flavivirus from aedes albopictus mosquito and a related species in japan. the virus, designated aedes flavivirus (aefv), only replicated in a mosquito cell line and produced a mild cytopathic effect. the aefv genome was positive-sense, single-stranded rna, 11,064 nucleotides in length and contained a single open reading frame encoding a polyprotein of 3341 amino acids with 5' and 3' untranslated regions (utrs) of 96 and 945 nucleotides, respectively. genetic and phylogenetic an ... | 2009 | 19580982 |
| virus-host coevolution: common patterns of nucleotide motif usage in flaviviridae and their hosts. | virus-host biological interaction is a continuous coevolutionary process involving both host immune system and viral escape mechanisms. flaviviridae family is composed of fast evolving rna viruses that infects vertebrate (mammals and birds) and/or invertebrate (ticks and mosquitoes) organisms. these host groups are very distinct life forms separated by a long evolutionary time, so lineage-specific anti-viral mechanisms are likely to have evolved. flaviviridae viruses which infect a single host l ... | 2009 | 19617912 |
| genomic sequence and phylogenetic analysis of culex flavivirus, an insect-specific flavivirus, isolated from culex pipiens (diptera: culicidae) in iowa. | adult mosquitoes (diptera: culicidae) were collected in 2007 and tested for specific viruses, including west nile virus, as part of the ongoing arbovirus surveillance efforts in the state of iowa. a subset of these mosquitoes (6,061 individuals in 340 pools) was further tested by reverse transcription-polymerase chain reaction (rt-pcr) using flavivirus universal primers. of the 211 pools of culex pipiens (l.) tested, 50 were positive. one of 51 pools of culex tarsalis coquillet was also positive ... | 2009 | 19645300 |
| isolation of a novel species of flavivirus and a new strain of culex flavivirus (flaviviridae) from a natural mosquito population in uganda. | the genus flavivirus, which contains approximately 70 single-stranded, positive-sense rna viruses, represents a unique model for studying the evolution of vector-borne disease, as it includes viruses that are mosquito-borne, tick-borne or have no known vector. both theoretical work and field studies suggest the existence of a large number of undiscovered flaviviruses. recently, the first isolation of cell fusing agent virus (cfav) was reported from a natural mosquito population in puerto rico, a ... | 2009 | 19656970 |
| evolution of the sequence composition of flaviviruses. | the adaption of pathogens to their host(s) is a major factor in the emergence of infectious disease and the persistent survival of many of the infectious diseases within the population. since many of the smaller viral pathogens are entirely dependent upon host machinery, it has been postulated that they are under selection for a composition similar to that of their host. analyses of sequence composition have been conducted for numerous small viral species including the flavivirus genus. examinat ... | 2010 | 19914402 |
| structure and functionality in flavivirus ns-proteins: perspectives for drug design. | flaviviridae are small enveloped viruses hosting a positive-sense single-stranded rna genome. besides yellow fever virus, a landmark case in the history of virology, members of the flavivirus genus, such as west nile virus and dengue virus, are increasingly gaining attention due to their re-emergence and incidence in different areas of the world. additional environmental and demographic considerations suggest that novel or known flaviviruses will continue to emerge in the future. nevertheless, u ... | 2010 | 19945487 |
| taming of the shrewd: novel eukaryotic genes from rna viruses. | genomes of several yeast species contain integrated dna copies of complete genomes or individual genes of non-retroviral double-strand rna viruses as reported in a recent bmc biology article by taylor and bruenn. the integrated virus-specific sequences are at least partially expressed and seem to evolve under pressure of purifying selection, indicating that these are functional genes. together with similar reports on integrated copies of some animal rna viruses, these results suggest that integr ... | 2010 | 20067611 |
| evidence for ribosomal frameshifting and a novel overlapping gene in the genomes of insect-specific flaviviruses. | flaviviruses have a positive-sense, single-stranded rna genome of approximately 11 kb, encoding a large polyprotein that is cleaved to produce approximately 10 mature proteins. cell fusing agent virus, kamiti river virus, culex flavivirus and several recently discovered flaviviruses have no known vertebrate host and apparently infect only insects. we present compelling bioinformatic evidence for a 253-295 codon overlapping gene (designated fifo) conserved throughout these insect-specific flavivi ... | 2010 | 20097399 |
| infection and vertical transmission of kamiti river virus in laboratory bred aedes aegypti mosquitoes. | kamiti river virus (krv) is an insect-only flavivirus that was isolated from field-collected ae. macintoshi mosquitoes in 1999, and is closely related to cell fusing agent virus. both of these viruses belong to the family flaviviridae, which also contains other viruses of medical importance, such as yellow fever virus, west nile virus and dengue. because ae. macintoshi is the only known natural host to krv, the main objective of this study was to establish the possibility that other mosquito hos ... | 2007 | 20337552 |
| detection of flaviviruses and orthobunyaviruses in mosquitoes in the yucatan peninsula of mexico in 2008. | a total of 191,244 mosquitoes from 24 species were collected in the yucatan peninsula of mexico from january to december 2008, and tested for the presence of cytopathic virus by virus isolation in vero cells. eighteen virus isolates were obtained, all of which were orthobunyaviruses. these were identified by reverse transcription-polymerase chain reaction (rt-pcr) and nucleotide sequencing as cache valley virus (n=17) and south river virus (n=1). a subset (n=20,124) of culex quinquefasciatus col ... | 2010 | 20370430 |
| arboviral survey of mosquitoes in two northern italian regions in 2007 and 2008. | recently, italy-particularly the emilia-romagna region-was the location of consecutive outbreaks of human diseases caused by the arboviruses chikungunya virus and west nile virus. the two outbreaks, spread by different species of mosquitoes, were not related, but pointed out the lack of an arboviral surveillance program in this region. beginning in 2007 entomological surveillance was initiated in the emilia-romagna region, and in 2008 the program was improved and extended at lombardia region. us ... | 2010 | 20370434 |
| isolation and sequence analysis of culex flavivirus from culex interrogator and culex quinquefasciatus in the yucatan peninsula of mexico. | previously, we reported a high prevalence of culex flavivirus (cxfv) in culex quinquefasciatus (say) in the yucatan peninsula of mexico. to determine whether other culex spp. mosquitoes in this region are susceptible to natural cxfv infection, cx. bahamensis (dyar and knab), cx. coronator (dyar and knab), cx. interrogator (dyar and knab), cx. nigripalpus (theobald) and cx. opisthopus (komp) in the yucatan peninsula of mexico were tested for cxfv. two pools of cx. interrogator were positive. the ... | 2010 | 20379749 |
| transmission of west nile virus by culex quinquefasciatus say infected with culex flavivirus izabal. | the natural history and potential impact of mosquito-specific flaviviruses on the transmission efficiency of west nile virus (wnv) is unknown. the objective of this study was to determine whether or not prior infection with culex flavivirus (cxfv) izabal altered the vector competence of cx. quinquefasciatus say for transmission of a co-circulating strain of west nile virus (wnv) from guatemala. | 2010 | 20454569 |
| an arthropod enzyme, dfurin1, and a vertebrate furin homolog display distinct cleavage site sequence preferences for a shared viral proprotein substrate. | alphaviruses replicate in vertebrate and arthropod cells and utilize a cellular enzyme called furin to process the pe2 glycoprotein precursor during virus replication in both cell types. furin cleaves pe2 at a site immediately following a highly conserved four residue cleavage signal. prior studies demonstrated that the amino acid immediately adjacent to the cleavage site influenced pe2 cleavage differently in vertebrate and mosquito cells (hw heidner et al. 1996 . journal of virology 70: 2069-2 ... | 2010 | 20578951 |
| structural and functional analyses of a conserved hydrophobic pocket of flavivirus methyltransferase. | the flavivirus methyltransferase (mtase) sequentially methylates the n7 and 2'-o positions of the viral rna cap (gpppa-rna → m(7)gpppa-rna → m(7)gpppam-rna), using s-adenosyl-l-methionine (adomet) as a methyl donor. we report here that sinefungin (sin), an adomet analog, inhibits several flaviviruses through suppression of viral mtase. the crystal structure of west nile virus mtase in complex with sin inhibitor at 2.0-å resolution revealed a flavivirus-conserved hydrophobic pocket located next t ... | 2010 | 20685660 |
| evidence of simultaneous circulation of west nile and usutu viruses in mosquitoes sampled in emilia-romagna region (italy) in 2009. | in recent years human diseases due to mosquito-borne viruses were increasingly reported in emilia-romagna region (italy), from the chikungunya virus in 2007 to the west nile virus (wnv) in 2008. an extensive entomological survey was performed in 2009 to establish the presence and distribution of mosquito arboviruses in this region, with particular reference to flaviviruses. | 2010 | 21179462 |
| culex flavivirus and west nile virus mosquito coinfection and positive ecological association in chicago, united states. | culex flavivirus (cxfv) is an insect-specific flavivirus globally distributed in mosquitoes of the genus culex. cxfv was positively associated with west nile virus (wnv) infection in a case-control study of 268 mosquito pools from an endemic focus of wnv transmission in chicago, united states. specifically, wnv-positive culex mosquito pools were four times more likely also to be infected with cxfv than were spatiotemporally matched wnv-negative pools. in addition, mosquito pools from residential ... | 2011 | 21254845 |
| replication enhancer elements within the open reading frame of tick-borne encephalitis virus and their evolution within the flavivirus genus. | we provide experimental evidence of a replication enhancer element (ree) within the capsid gene of tick-borne encephalitis virus (tbev, genus flavivirus). thermodynamic and phylogenetic analyses predicted that the ree folds as a long stable stem-loop (designated sl6), conserved among all tick-borne flaviviruses (tbfv). homologous sequences and potential base pairing were found in the corresponding regions of mosquito-borne flaviviruses, but not in more genetically distant flaviviruses. to invest ... | 2011 | 21622960 |
| distribution and phylogenetic comparisons of a novel mosquito flavivirus sequence present in culex tarsalis mosquitoes from western canada with viruses isolated in california and colorado. | in a previous study, a new flavivirus genome sequence was identified in culex tarsalis mosquitoes obtained in alberta, canada and was shown to be genetically related to but distinct from members of the insect-specific flaviviruses. nonstructural protein 5-encoding sequences amplified from cx. tarsalis pools from western canada have shown a high similarity to genome sequences of novel flaviviruses isolated from mosquitoes in california and colorado. despite wide distribution of this virus, design ... | 2011 | 21734143 |
| insect-specific flaviviruses from culex mosquitoes in colorado, with evidence of vertical transmission. | mosquitoes were collected in colorado during 2006 and 2007 to examine spatial and seasonal patterns of risk for exposure to culex vectors and west nile virus. we used universal flavivirus primers to test pools of culex mosquitoes for viral rna. this led to the detection and subsequent isolation of two insect-specific flaviviruses: culex flavivirus (cxfv), which was first described from japan, and a novel insect flavivirus, designated calbertado virus (clbov), which has also been detected in cali ... | 2011 | 21734144 |
| novel flaviviruses detected in different species of mosquitoes in spain. | abstract we report the characterization of three novel flaviviruses isolated in spain. marisma mosquito virus, a novel mosquito borne virus, was isolated from ochlerotatus caspius mosquitoes; spanish ochlerotatus flavivirus and spanish culex flavivirus, two novel insect flaviviruses, were isolated from oc. caspius and culex pipiens, respectively. during this investigation, we designed a sensitive rt-nested polymerase chain reaction method that amplifies a 1019bp fragment of the flavivirus ns5 ... | 2011 | 22022811 |
| Molecular evolution of the insect-specific flaviviruses. | There has been an explosion in the discovery of 'insect-specific' flaviviruses and/or their related sequences in natural mosquito populations. Herein we review all 'insect-specific' flaviviral sequences currently available and conduct phylogenetic analyses of both the 'insect-specific' flaviviruses and available sequences of the entire genus Flavivirus. We show that there is no statistical support for virus-mosquito co-divergence, suggesting that the 'insect-specific' flaviviruses may have under ... | 2011 | 22012464 |
| insect-specific virus discovery: significance for the arbovirus community. | arthropod-borne viruses (arboviruses), especially those transmitted by mosquitoes, are a significant cause of morbidity and mortality in humans and animals worldwide. recent discoveries indicate that mosquitoes are naturally infected with a wide range of other viruses, many within taxa occupied by arboviruses that are considered insect-specific. over the past ten years there has been a dramatic increase in the literature describing novel insect-specific virus detection in mosquitoes, which has p ... | 2015 | 26378568 |
| insect-specific flaviviruses: a systematic review of their discovery, host range, mode of transmission, superinfection exclusion potential and genomic organization. | there has been a dramatic increase in the number of insect-specific flaviviruses (isfs) discovered in the last decade. historically, these viruses have generated limited interest due to their inability to infect vertebrate cells. this viewpoint has changed in recent years because some isfs have been shown to enhance or suppress the replication of medically important flaviviruses in co-infected mosquito cells. additionally, comparative studies between isfs and medically important flaviviruses can ... | 2015 | 25866904 |
| eilat virus host range restriction is present at multiple levels of the virus life cycle. | most alphaviruses are mosquito-borne and exhibit a broad host range, infecting many different vertebrates, including birds, rodents, equids, humans, and nonhuman primates. this ability of most alphaviruses to infect arthropods and vertebrates is essential for their maintenance in nature. recently, a new alphavirus, eilat virus (eilv), was described, and in contrast to all other mosquito-borne viruses, it is unable to replicate in vertebrate cell lines. investigations into the nature of its host ... | 2014 | 25392227 |
| biological transmission of arboviruses: reexamination of and new insights into components, mechanisms, and unique traits as well as their evolutionary trends. | among animal viruses, arboviruses are unique in that they depend on arthropod vectors for transmission. field research and laboratory investigations related to the three components of this unique mode of transmission, virus, vector, and vertebrate host, have produced an enormous amount of valuable information that may be found in numerous publications. however, despite many reviews on specific viruses, diseases, or interests, a systematic approach to organizing the available information on all f ... | 0 | 16223950 |
| the insect-specific palm creek virus modulates west nile virus infection in and transmission by australian mosquitoes. | insect-specific viruses do not replicate in vertebrate cells, but persist in mosquito populations and are highly prevalent in nature. these viruses may naturally regulate the transmission of pathogenic vertebrate-infecting arboviruses in co-infected mosquitoes. following the isolation of the first australian insect-specific flavivirus (isf), palm creek virus (pcv), we investigated routes of infection and transmission of this virus in key australian arbovirus vectors and its impact on replication ... | 2016 | 27457250 |
| fighting arbovirus transmission: natural and engineered control of vector competence in aedes mosquitoes. | control of aedine mosquito vectors, either by mosquito population reduction or replacement with refractory mosquitoes, may play an essential role in the fight against arboviral diseases. in this review, we will focus on the development and application of biological approaches, both natural or engineered, to limit mosquito vector competence for arboviruses. the study of mosquito antiviral immunity has led to the identification of a number of host response mechanisms and proteins that are required ... | 2015 | 26463078 |
| vector-virus interactions and transmission dynamics of west nile virus. | west nile virus (wnv; flavivirus; flaviviridae) is the cause of the most widespread arthropod-borne viral disease in the world and the largest outbreak of neuroinvasive disease ever observed. mosquito-borne outbreaks are influenced by intrinsic (e.g., vector and viral genetics, vector and host competence, vector life-history traits) and extrinsic (e.g., temperature, rainfall, human land use) factors that affect virus activity and mosquito biology in complex ways. the concept of vectorial capacit ... | 2013 | 24351794 |
| a new insect-specific flavivirus from northern australia suppresses replication of west nile virus and murray valley encephalitis virus in co-infected mosquito cells. | recent reports of a novel group of flaviviruses that replicate only in mosquitoes and appear to spread through insect populations via vertical transmission have emerged from around the globe. to date, there is no information on the presence or prevalence of these insect-specific flaviviruses (isfs) in australian mosquito species. to assess whether such viruses occur locally, we used reverse transcription-polymerase chain reaction (rt-pcr) and flavivirus universal primers that are specific to the ... | 2013 | 23460804 |
| eilat virus, a unique alphavirus with host range restricted to insects by rna replication. | most alphaviruses and many other arboviruses are mosquito-borne and exhibit a broad host range, infecting many different vertebrates including birds, rodents, equids, humans, and nonhuman primates. consequently, they can be propagated in most vertebrate and insect cell cultures. this ability of arboviruses to infect arthropods and vertebrates is usually essential for their maintenance in nature. however, several flaviviruses have recently been described that infect mosquitoes but not vertebrates ... | 2012 | 22908261 |
| replication of west nile virus, rabensburg lineage in mammalian cells is restricted by temperature. | the genus flavivirus currently consists of approximately 80 single-strand positive-sense rna viruses. these replicate in a range of hosts including myriad vertebrate, insect, and tick species. as a consequence of this broad host range, the majority of flaviviruses can be propagated in most vertebrate and insect cell cultures. this ability to infect arthropods and vertebrates usually is essential for maintenance of these viruses in nature. but recently, there has been the discovery of a number of ... | 2012 | 23241081 |
| transmission dynamics of an insect-specific flavivirus in a naturally infected culex pipiens laboratory colony and effects of co-infection on vector competence for west nile virus. | we established a laboratory colony of culex pipiens mosquitoes from eggs collected in colorado and discovered that mosquitoes in the colony are naturally infected with culex flavivirus (cxfv), an insect-specific flavivirus. in this study we examined transmission dynamics of cxfv and effects of persistent cxfv infection on vector competence for west nile virus (wnv). we found that vertical transmission is the primary mechanism for persistence of cxfv in cx. pipiens, with venereal transmission pot ... | 2012 | 22425062 |
| the emerging duck flavivirus is not pathogenic for primates and is highly sensitive to mammalian interferon antiviral signaling. | flaviviruses pose a significant threat to both animals and humans. recently, a novel flavivirus, duck tembusu virus (dtmuv), was identified to be the causative agent of a serious duck viral disease in asia. its rapid spread, expanding host range, and uncertain transmission routes have raised substantial concerns regarding its potential threats to nonavian hosts, including humans. here, we demonstrate that dtmuv is not pathogenic for nonhuman primates and is highly sensitive to mammal type i inte ... | 2016 | 27147750 |
| viral interference and persistence in mosquito-borne flaviviruses. | mosquito-borne flaviviruses are important pathogens for humans, and the detection of two or more flaviviruses cocirculating in the same geographic area has often been reported. however, the epidemiological impact remains to be determined. mosquito-borne flaviviruses are primarily transmitted through aedes and culex mosquitoes; these viruses establish a life-long or persistent infection without apparent pathological effects. this establishment requires a balance between virus replication and the ... | 2015 | 26583158 |
| novel virus discovery and genome reconstruction from field rna samples reveals highly divergent viruses in dipteran hosts. | we investigated whether small rna (srna) sequenced from field-collected mosquitoes and chironomids (diptera) can be used as a proxy signature of viral prevalence within a range of species and viral groups, using srnas sequenced from wild-caught specimens, to inform total rna deep sequencing of samples of particular interest. using this strategy, we sequenced from adult anopheles maculipennis s.l. mosquitoes the apparently nearly complete genome of one previously undescribed virus related to chro ... | 2013 | 24260463 |
| identification of a previously undescribed divergent virus from the flaviviridae family in an outbreak of equine serum hepatitis. | theiler's disease is an acute hepatitis in horses that is associated with the administration of equine blood products; its etiologic agent has remained unknown for nearly a century. here, we used massively parallel sequencing to explore samples from a recent theiler's disease outbreak. metatranscriptomic analysis of the short sequence reads identified a 10.5-kb sequence from a previously undescribed virus of the flaviviridae family, which we designate "theiler's disease-associated virus" (tdav). ... | 2013 | 23509292 |
| mercadeo virus: a novel mosquito-specific flavivirus from panama. | viruses in the genus flavivirus (family flaviviridae) include many arthropod-borne viruses of public health and veterinary importance. however, during the past two decades an explosion of novel insect-specific flaviviruses (isfs), some closely related to vertebrate pathogens, have been discovered. although many flavivirus pathogens of vertebrates have been isolated from naturally infected mosquitoes in panama, isfs have not previously been reported from the country. this report describes the iso ... | 2015 | 26304915 |
| ecuador paraiso escondido virus, a new flavivirus isolated from new world sand flies in ecuador, is the first representative of a novel clade in the genus flavivirus. | a new flavivirus, ecuador paraiso escondido virus (epev), named after the village where it was discovered, was isolated from sand flies (psathyromyia abonnenci, formerly lutzomyia abonnenci) that are unique to the new world. this represents the first sand fly-borne flavivirus identified in the new world. epev exhibited a typical flavivirus genome organization. nevertheless, the maximum pairwise amino acid sequence identity with currently recognized flaviviruses was 52.8%. phylogenetic analysis o ... | 2015 | 26355096 |
| novel flaviviruses from mosquitoes: mosquito-specific evolutionary lineages within the phylogenetic group of mosquito-borne flaviviruses. | novel flaviviruses that are genetically related to pathogenic mosquito-borne flaviviruses (mbfv) have been isolated from mosquitoes in various geographical locations, including finland. we isolated and characterized another novel virus of this group from finnish mosquitoes collected in 2007, designated as ilomantsi virus (ilov). unlike the mbfv that infect both vertebrates and mosquitoes, the mbfv-related viruses appear to be specific to mosquitoes similar to the insect-specific flaviviruses (is ... | 2014 | 25108382 |
| molecular characterization of flaviviruses from field-collected mosquitoes in northwestern italy, 2011-2012. | the genus flavivirus comprises several mosquito-borne species, including the zoonotic pathogens west nile and usutu virus, circulating in animals and humans in italy since 1998. due to its ecological and geographical features, piedmont is considered a risk area for flavivirus transmission. here we report the results of a flavivirus survey (detection and genetic characterization) of mosquitoes collected in piedmont in 2012 and the genetic characterization of three strains detected in 2011. | 2014 | 25160565 |
| characterization of a novel insect-specific flavivirus from brazil: potential for inhibition of infection of arthropod cells with medically important flaviviruses. | in the past decade, there has been an upsurge in the number of newly described insect-specific flaviviruses isolated pan-globally. we recently described the isolation of a novel flavivirus (tentatively designated 'nhumirim virus'; nhuv) that represents an example of a unique subset of apparently insect-specific viruses that phylogenetically affiliate with dual-host mosquito-borne flaviviruses despite appearing to be limited to replication in mosquito cells. we characterized the in vitro growth p ... | 2014 | 25146007 |
| substitution of the premembrane and envelope protein genes of modoc virus with the homologous sequences of west nile virus generates a chimeric virus that replicates in vertebrate but not mosquito cells. | most known flaviviruses, including west nile virus (wnv), are maintained in natural transmission cycles between hematophagous arthropods and vertebrate hosts. other flaviviruses such as modoc virus (modv) and culex flavivirus (cxfv) have host ranges restricted to vertebrates and insects, respectively. the genetic elements that modulate the differential host ranges and transmission cycles of these viruses have not been identified. | 2014 | 25151534 |
| evidence of mosquito-transmitted flavivirus circulation in piedmont, north-western italy. | flavivirus is a highly heterogeneous viral genus that includes important human pathogens and several viral strains with unknown zoonotic potential. mosquito-borne flaviviruses have been isolated and characterized in northern italy: west nile virus and usutu virus were detected in mosquitoes and in different host species and recent studies provided evidence about the circulation of "insect flavivirus" strains. | 2012 | 22616748 |
| rapid evolutionary dynamics of structural disorder as a potential driving force for biological divergence in flaviviruses. | protein structure is commonly regarded to be conserved and to dictate function. most proteins rely on conformational flexibility to some degree. are regions that convey conformational flexibility conserved over evolutionary time? can changes in conformational flexibility alter protein function? here, the evolutionary dynamics of structurally ordered and disordered (flexible) regions are investigated genome-wide in flaviviruses, revealing that the amount and location of structural disorder fluctu ... | 0 | 23418179 |
| ilheus virus isolation in the pantanal, west-central brazil. | the wetlands of the brazilian pantanal host large concentrations of diverse wildlife species and hematophagous arthropods, conditions that favor the circulation of zoonotic arboviruses. a recent study from the nhecolândia sub-region of pantanal reported serological evidence of various flaviviruses, including west nile virus and ilheus virus (ilhv). according to the age of seropositive horses, at least three flaviviruses, including ilhv, circulated in the brazilian pantanal between 2005 and 2009. ... | 2013 | 23875051 |
| flaviviruses in europe: complex circulation patterns and their consequences for the diagnosis and control of west nile disease. | in europe, many flaviviruses are endemic (west nile, usutu, tick-borne encephalitis viruses) or occasionally imported (dengue, yellow fever viruses). due to the temporal and geographical co-circulation of flaviviruses in europe, flavivirus differentiation by diagnostic tests is crucial in the adaptation of surveillance and control efforts. serological diagnosis of flavivirus infections is complicated by the antigenic similarities among the flavivirus genus. indeed, most flavivirus antibodies are ... | 2013 | 24225644 |
| novel insect-specific flavivirus isolated from northern europe. | mosquitoes collected in finland were screened for flaviviral rna leading to the discovery and isolation of a novel flavivirus designated hanko virus (hankv). virus characterization, including phylogenetic analysis of the complete coding sequence, confirmed hankv as a member of the "insect-specific" flavivirus (isf) group. hankv is the first member of this group isolated from northern europe, and therefore the first northern european isf for which the complete coding sequence has been determined. ... | 2012 | 22999256 |
| detection of a new insect flavivirus and isolation of aedes flavivirus in northern italy. | during recent years, numerous novel 'insect flaviviruses' have been discovered in natural mosquito populations. in a previous study we described the presence of flavivirus dna sequences integrated in aedes albopictus (asian tiger mosquito) populations from northern italy in 2007. | 2012 | 23043958 |
| molecular archaeology of flaviviridae untranslated regions: duplicated rna structures in the replication enhancer of flaviviruses and pestiviruses emerged via convergent evolution. | rna secondary structures in the 3'untranslated regions (3'utr) of the viruses of the family flaviviridae, previously identified as essential (promoters) or beneficial (enhancers) for replication, have been analysed. duplicated enhancer elements are revealed as a global feature in the evolution of the 3'utr of distantly related viruses within the genera flavivirus and pestivirus. for the flaviviruses, duplicated structures occur in the 3'utr of all four distantly related ecological virus subgroup ... | 2014 | 24647143 |
| isolation and identification of a distinct strain of culex flavivirus from mosquitoes collected in mainland china. | culexflavivirus (cxfv) is an insect specific virus that has been isolated from culexpipiens, culexquinquefasciatus, culextritaeniorhynchus and other culex mosquitoes. it is a novel flavivirus isolated in asia, north america, central america and africa. phylogenetic analysis indicates that, based on the envelope gene (e gene) sequence, the worldwide cxfv strains can be divided into two genotypes. | 2012 | 22452813 |
| discovery of novel viruses in mosquitoes from the zambezi valley of mozambique. | mosquitoes carry a wide variety of viruses that can cause vector-borne infectious diseases and affect both human and veterinary public health. although mozambique can be considered a hot spot for emerging infectious diseases due to factors such as a rich vector population and a close vector/human/wildlife interface, the viral flora in mosquitoes have not previously been investigated. in this study, viral metagenomics was employed to analyze the viral communities in culex and mansonia mosquitoes ... | 2016 | 27682810 |
| flavidb: a data mining system for knowledge discovery in flaviviruses with direct applications in immunology and vaccinology. | the flavivirus genus is unusually large, comprising more than 70 species, of which more than half are known human pathogens. it includes a set of clinically relevant infectious agents such as dengue, west nile, yellow fever, and japanese encephalitis viruses. although these pathogens have been studied extensively, safe and efficient vaccines lack for the majority of the flaviviruses. | 0 | 25544857 |
| genetic characterization of an insect-specific flavivirus isolated from culex theileri mosquitoes collected in southern portugal. | we describe the full genetic characterization of an insect-specific flavivirus (isf) from culex theileri (theobald) mosquitoes collected in portugal. this represents the first isolation and full characterization of an isf from portuguese mosquitoes. the virus, designated ctfv, for culex theileri flavivirus, was isolated in the c6/36 stegomyia albopicta (=aedes albopictus) cell line, and failed to replicate in vertebrate (vero) cells in common with other isfs. the ctfv genome encodes a single pol ... | 2012 | 22579596 |
| characterisation of divergent flavivirus ns3 and ns5 protein sequences detected in rhipicephalus microplus ticks from brazil. | transcripts similar to those that encode the nonstructural (ns) proteins ns3 and ns5 from flaviviruses were found in a salivary gland (sg) complementary dna (cdna) library from the cattle tick rhipicephalus microplus. tick extracts were cultured with cells to enable the isolation of viruses capable of replicating in cultured invertebrate and vertebrate cells. deep sequencing of the viral rna isolated from culture supernatants provided the complete coding sequences for the ns3 and ns5 proteins an ... | 2013 | 24626302 |
| selective factors associated with the evolution of codon usage in natural populations of arboviruses. | arboviruses (arthropod borne viruses) have life cycles that include both vertebrate and invertebrate hosts with substantial differences in vector and host specificity between different viruses. most arboviruses utilize rna for their genetic material and are completely dependent on host trnas for their translation, suggesting that virus codon usage could be a target for selection. in the current study we analyzed the relative synonymous codon usage (rscu) patterns of 26 arboviruses together with ... | 2016 | 27455096 |
| a deep insight into the sialome of male and female aedes aegypti mosquitoes. | only adult female mosquitoes feed on blood, while both genders take sugar meals. accordingly, several compounds associated with blood feeding (i.e. vasodilators, anti-clotting, anti-platelets) are found only in female glands, while enzymes associated with sugar feeding or antimicrobials (such as lysozyme) are found in the glands of both sexes. we performed de novo assembly of reads from adult aedes aegypti female and male salivary gland libraries (285 and 90 million reads, respectively). by mapp ... | 2016 | 26999592 |
| endogenous viral elements in animal genomes. | integration into the nuclear genome of germ line cells can lead to vertical inheritance of retroviral genes as host alleles. for other viruses, germ line integration has only rarely been documented. nonetheless, we identified endogenous viral elements (eves) derived from ten non-retroviral families by systematic in silico screening of animal genomes, including the first endogenous representatives of double-stranded rna, reverse-transcribing dna, and segmented rna viruses, and the first endogenou ... | 2010 | 21124940 |
| insect-specific flavivirus infection is restricted by innate immunity in the vertebrate host. | arboviruses are a large group of viruses that are transmitted by arthropods including ticks and mosquitoes. the global diversity of arboviruses is unknown; however, theoretical studies have estimated that over 2,000 mosquito-borne flaviviruses may exist. an increasing number of flaviviruses can only infect insect cells. we hypothesize that insect-specific flaviviruses (isfvs) represent model genetic precursors to pathogenic flaviviruses, although the genetic mechanisms required for adaptation to ... | 2016 | 27433779 |
| detection of quang binh virus from mosquitoes in china. | flaviviruses present a wide range of genetic diversity and exhibit diverse host relationships. mosquito-borne flaviviruses have recently been isolated and characterized worldwide. yunnan province of china is one of the richest areas of species diversity and is the center of multi-species evolution in mainland asia, which supports the circulation of numerous arthropod-borne viruses (arboviruses). in a screening program of arboviruses, mosquitoes were collected during the mosquito activity season ... | 2014 | 24342141 |
| insect-specific flaviviruses, a worldwide widespread group of viruses only detected in insects. | several flaviviruses are important pathogens for humans and animals (dengue viruses, japanese encephalitis virus, yellow-fever virus, tick-borne encephalitis virus, west nile virus). in recent years, numerous novel and related flaviviruses without known pathogenic capacity have been isolated worldwide in the natural mosquito population. however, phylogenetic studies have shown that genomic sequences of these viruses diverge from other flaviviruses. moreover, these viruses seem to be exclusive of ... | 2016 | 26235844 |
| detection of mosquito-only flaviviruses in europe. | the genus flavivirus, family flaviviridae, includes a number of important arthropod-transmitted human pathogens such as dengue viruses, west nile virus, japanese encephalitis virus and yellow fever virus. in addition, the genus includes flaviviruses without a known vertebrate reservoir, which have been detected only in insects, particularly in mosquitoes, such as cell fusing agent virus, kamiti river virus, culex flavivirus, aedes flavivirus, quang binh virus, nakiwogo virus and calbertado virus ... | 2012 | 22377581 |
| entomological surveillance for flaviviruses at migratory bird stopover sites in hokkaido, japan, and a new insect flavivirus detected in aedes galloisi (diptera: culicidae). | to investigate the possible spread of west nile virus (wnv) into japan, we carried out entomological surveillance for flaviviruses at migratory bird stopover sites in hokkaido, japan, during 2003-2006. a total of 3,826 mosquitoes, identified as 15 species in five genera, were collected and 2,465 of these were grouped into 123 pools that were assayed for cytopathic effects on mosquito and mammalian cell cultures and for flavivirus rna by reverse transcription-polymerase chain reaction using flavi ... | 2012 | 22308786 |
| the discovery of arthropod-specific viruses in hematophagous arthropods: an open door to understanding the mechanisms of arbovirus and arthropod evolution? | the discovery of an odd virus from hematophagous arthropods 40 years ago by stollar and thomas described cell fusing agent virus in cells derived from aedes aegypti mosquitoes. then came the report of kamiti river virus from ae. macintoshi in 1999, followed by worldwide reports of the discovery of other viruses of mosquitoes, ticks, and midges that replicate only in arthropods and not in vertebrates or in vertebrate cells. these viruses (now totaling at least 64 published) have genomes analogous ... | 2018 | 29324047 |