sucrose density gradient centrifugation and cross-flow filtration methods for the production of arbovirus antigens inactivated by binary ethylenimine.sucrose density gradient centrifugation and cross-flow filtration methods have been developed and standardised for the safe and reproducible production of inactivated arbovirus antigens which are appropriate for use in diagnostic serological applications.200414720306
Tembusu virus in ducks, china.In China in 2010, a disease outbreak in egg-laying ducks was associated with a flavivirus. The virus was isolated and partially sequenced. The isolate exhibited 87%-91% identity with strains of Tembusu virus, a mosquito-borne flavivirus of the Ntaya virus group. These findings demonstrate emergence of Tembusu virus in ducks.201122000358
emergence of usutu virus, an african mosquito-borne flavivirus of the japanese encephalitis virus group, central europe.during late summer 2001 in austria, a series of deaths in several species of birds occurred, similar to the beginning of the west nile virus (wnv) epidemic in the united states. we necropsied the dead birds and examined them by various methods; pathologic and immunohistologic investigations suggested a wnv infection. subsequently, the virus was isolated, identified, partially sequenced, and subjected to phylogenetic analysis. the isolates exhibited 97% identity to usutu virus (usuv), a mosquito- ...200212095429
enhanced arbovirus surveillance with deep sequencing: identification of novel rhabdoviruses and bunyaviruses in australian mosquitoes.viral metagenomics characterizes known and identifies unknown viruses based on sequence similarities to any previously sequenced viral genomes. a metagenomics approach was used to identify virus sequences in australian mosquitoes causing cytopathic effects in inoculated mammalian cell cultures. sequence comparisons revealed strains of liao ning virus (reovirus, seadornavirus), previously detected only in china, livestock-infecting stretch lagoon virus (reovirus, orbivirus), two novel dimarhabdov ...201324314645
usutu virus: an emerging flavivirus in europe.usutu virus (usuv) is an african mosquito-borne flavivirus belonging to the japanese encephalitis virus serocomplex. usuv is closely related to murray valley encephalitis virus, japanese encephalitis virus, and west nile virus. usuv was discovered in south africa in 1959. in europe, the first true demonstration of circulation of usuv was reported in austria in 2001 with a significant die-off of eurasian blackbirds. in the subsequent years, usuv expanded to neighboring countries, including italy, ...201525606971
viral rna intermediates as targets for detection and discovery of novel and emerging mosquito-borne viruses.mosquito-borne viruses encompass a range of virus families, comprising a number of significant human pathogens (e.g., dengue viruses, west nile virus, chikungunya virus). virulent strains of these viruses are continually evolving and expanding their geographic range, thus rapid and sensitive screening assays are required to detect emerging viruses and monitor their prevalence and spread in mosquito populations. double-stranded rna (dsrna) is produced during the replication of many of these virus ...201525799391
genetic differentiation of murray valley encephalitis virus in australia and papua new guinea.the genetic relatedness of ten murray valley encephalitis virus (mve) isolates from australia has been examined by comparing haeiii and taqi restriction digest profiles of cdna to virion rna. the isolates were from the murray valley region of south-eastern australia and from the ord river region of western australia and spanned a period of 23 years (1951-1974). the isolates generated closely similar restriction digest profiles. the extent of similarity suggested that the level of nucleotide sequ ...19862884985
new insights into flavivirus evolution, taxonomy and biogeographic history, extended by analysis of canonical and alternative coding generate the most diverse phylogenetic dataset for the flaviviruses to date, we determined the genomic sequences and phylogenetic relationships of 14 flaviviruses, of which 10 are primarily associated with culex spp. mosquitoes. we analyze these data, in conjunction with a comprehensive collection of flavivirus genomes, to characterize flavivirus evolutionary and biogeographic history in unprecedented detail and breadth. based on the presumed introduction of yellow fever virus into the americ ...201525719412
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 ...201526355096
noncoding subgenomic flavivirus rna: multiple functions in west nile virus pathogenesis and modulation of host responses.flaviviruses are a large group of positive strand rna viruses transmitted by arthropods that include many human pathogens such as west nile virus (wnv), japanese encephalitis virus (jev), yellow fever virus, dengue virus, and tick-borne encephalitis virus. all members in this genus tested so far are shown to produce a unique subgenomic flavivirus rna (sfrna) derived from the 3' untranslated region (utr). sfrna is a product of incomplete degradation of genomic rna by the cell 5'-3' exoribonucleas ...201424473339
development of monoclonal antibodies to west nile virus and their application in immunohistochemistry.west nile virus (wnv) is endemic throughout africa, eurasia, america, and australia and has important implications for avian, horse, and human health. in these regions, dead birds are monitored for the presence of wnv through immunohistochemistry (ihc) and pcr. however, a number of the tools for ihc are inadequate owing to their cross-reactivity to other japanese encephalitis serogroup viruses. here we have established eight monoclonal antibodies (mabs) to wnv. four of them bound to the envelope ...201222993408
determinants of attenuation in the envelope protein of the flavivirus alfuy.murray valley encephalitis virus (mvev) is a mosquito-borne flavivirus endemic to australia and papua new guinea. most strains of mvev cause potentially fatal cases of encephalitis in humans and horses, and have been shown to be highly neuroinvasive in weanling mice. in contrast, the naturally-occurring subtype alfuy virus (alfv) has never been associated with human disease, nor is it neuroinvasive in weanling mice, even at high doses. to identify viral factors associated with alfv attenuation, ...201121733886
phylogeography of west nile virus: from the cradle of evolution in africa to eurasia, australia, and the americas.west nile virus (wnv) is the most widely distributed of the encephalitic flaviviruses and is a major cause of encephalitis, with isolates obtained from all continents, apart from antarctica. subsequent to its divergence from the other members of the japanese encephalitis virus complex, presumably in africa, wnv has diverged into individual lineages that mostly correspond with geographic distribution. here we elucidate the phylogeography and evolutionary history of isolates from lineage 1 of wnv. ...201021159871
molecular phylogeny of edge hill virus supports its position in the yellow fever virus group and identifies a new genetic variant.edge hill virus (ehv) is a mosquito-borne flavivirus isolated throughout australia during mosquito surveillance programs. while not posing an immediate threat to the human population, ehv is a taxonomically interesting flavivirus since it remains the only member of the yellow fever virus (yfv) sub-group to be detected within australia. here we present both an antigenic and genetic investigation of collected isolates, and confirm taxonomic classification of the virus within the yfv-group. isolate ...201020938485
concomitant or sequential administration of live attenuated japanese encephalitis chimeric virus vaccine and yellow fever 17d vaccine: randomized double-blind phase ii evaluation of safety and immunogenicity.a randomized, double-blind, study was conducted to evaluate the safety, tolerability and immunogenicity of a live attenuated japanese encephalitis chimeric virus vaccine (je-cv) co-administered with live attenuated yellow fever vaccine (yf-17d strain; stamaril®, sanofi pasteur) or administered successively. participants (n = 108) were randomized to receive: yf followed by je-cv 30 days later, je followed by yf 30 days later, or the co-administration of je and yf followed or preceded by placebo 3 ...201020864814
safety and immunogenicity of a delta inulin-adjuvanted inactivated japanese encephalitis virus vaccine in pregnant mares and 2011, following severe flooding in eastern australia, an unprecedented epidemic of equine encephalitis occurred in south-eastern australia, caused by murray valley encephalitis virus (mvev) and a new variant strain of kunjin virus, a subtype of west nile virus (wnvkun). this prompted us to assess whether a delta inulin-adjuvanted, inactivated cell culture-derived japanese encephalitis virus (jev) vaccine (je-advax™) could be used in horses, including pregnant mares and foals, to not only indu ...201425516480
genetic variation of st. louis encephalitis louis encephalitis virus (slev) has been regularly isolated throughout the americas since 1933. previous phylogenetic studies involving 62 isolates have defined seven major lineages (i-vii), further divided into 14 clades. in this study, 28 strains isolated in texas in 1991 and 2001-2003, and three older, previously unsequenced strains from jamaica and california were sequenced over the envelope protein gene. the inclusion of these new sequences, and others published since 2001, has allowed ...200818632961
a glance at subgenomic flavivirus rnas and micrornas in flavivirus infections.the family flaviviridae comprises a wide variety of viruses that are distributed worldwide, some of which are associated with high rates of morbidity and mortality. there are neither vaccines nor antivirals for most flavivirus infections, reinforcing the importance of research on different aspects of the viral life cycle. during infection, cytoplasmic accumulation of rna fragments mainly originating from the 3' utrs, which have been designated subgenomic flavivirus rnas (sfrnas), has been detect ...201627233361
panmicrobial oligonucleotide array for diagnosis of infectious facilitate rapid, unbiased, differential diagnosis of infectious diseases, we designed greenechippm, a panmicrobial microarray comprising 29,455 sixty-mer oligonucleotide probes for vertebrate viruses, bacteria, fungi, and parasites. methods for nucleic acid preparation, random primed pcr amplification, and labeling were optimized to allow the sensitivity required for application with nucleic acid extracted from clinical materials and cultured isolates. analysis of nasopharyngeal aspirates, b ...200717370518
biological, antigenic and phylogenetic characterization of the flavivirus alfuy.alfuy virus (alfv) is classified as a subtype of the flavivirus murray valley encephalitis virus (mvev); however, despite preliminary reports of antigenic and ecological similarities with mvev, alfv has not been associated with human disease. here, it was shown that alfv is at least 10(4)-fold less neuroinvasive than mvev after peripheral inoculation of 3-week-old swiss outbred mice, but alfv demonstrates similar neurovirulence. in addition, it was shown that alfv is partially attenuated in mice ...200616432019
flavivirus isolations from mosquitoes collected from western cape york peninsula, australia, 1999-2000.after the 1st appearance of japanese encephalitis virus (je) on mainland australia in 1998, a study was undertaken to investigate whether je had become established in enzootic transmission cycles on western cape york peninsula. adult mosquitoes were collected during the late wet season from kowanyama and pormpuraaw in april 1999, and pormpuraaw and barr's yard in april 2000. despite processing 269,270 mosquitoes for virus isolation, no isolates of je were obtained. however, other flaviviruses co ...200314710742
characterization of a novel insect-specific flavivirus from brazil: potential for inhibition of infection of arthropod cells with medically important 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 ...201425146007
detection of west nile virus antigen in mosquitoes and avian tissues by a monoclonal antibody-based capture enzyme antigen capture immunoassay to detect west nile (wn) virus antigen in infected mosquitoes and avian tissues has been developed. with this assay purified wn virus was detected at a concentration of 32 pg/0.1 ml, and antigen in infected suckling mouse brain and laboratory-infected mosquito pools could be detected when the wn virus titer was 10(2.1) to 10(3.7) pfu/0.1 ml. in a blindly coded set of field-collected mosquito pools (n = 100), this assay detected wn virus antigen in 12 of 18 (66.7%) ...200212037058
phylogenetic analysis of a human isolate from the 2000 israel west nile virus epidemic.specimens from a patient of the 2000 israel west nile virus epidemic were analyzed by reverse transcription-polymerase chain reaction. products corresponding to e, ns3, and ns5 sequences were amplified from cerebellar but not from cortical samples. phylogenetic analyses indicated a closer relationship of this isolate to 1996 romanian and 1999 russian than to 1998-99 israeli or 1999 new york isolates.200211996693
origin and evolution of japanese encephalitis virus in southeast asia.since it emerged in japan in the 1870s, japanese encephalitis has spread across asia and has become the most important cause of epidemic encephalitis worldwide. four genotypes of japanese encephalitis virus (jev) are presently recognized (representatives of genotypes i to iii have been fully sequenced), but its origin is not known. we have determined the complete nucleotide and amino acid sequence of a genotype iv indonesian isolate (jkt6468) which represents the oldest lineage, compared it with ...200312584335
west nile virus (kunjin subtype) disease in the northern territory of australia--a case of encephalitis and review of all reported cases.west nile virus kunjin subtype (wnv/kunv) is enzootic across the tropical north of australia, with epizootic spread into other jurisdictions. the clinical spectrum of illness in humans is poorly described. we report a clinical case of wnv/kunv encephalitis and performed a retrospective chart audit of all cases of wnv/kunv notified in the northern territory from 1992 to 2010. thirteen cases of wnv/kunv disease were identified; case notes were available for 10 of these presentations. six of these ...201122049056
natural exposure of horses to mosquito-borne flaviviruses in south-east queensland, 2011 an unprecedented epidemic of equine encephalitis occurred in south-eastern (se) australia following heavy rainfall and severe flooding in the preceding 2-4 months. less than 6% of the documented cases occurred in queensland, prompting the question of pre-existing immunity in queensland horses. a small-scale serological survey was conducted on horses residing in one of the severely flood-affected areas of se-queensland. using a flavivirus-specific blocking-elisa we found that 63% (39/62) ...201324048209
novel flavivirus or new lineage of west nile virus, central europe.a flavivirus (strain 97-103) was isolated from culex pipens mosquitoes in 1997 following floods in south moravia, czech republic. the strain exhibited close antigenic relationship to west nile virus (wnv) prototype strain eg-101 in a cross-neutralization test. in this study, mouse pathogenicity characteristics and the complete nucleotide and putative amino acid sequences of isolate 97-103, named rabensburg virus (rabv) after a nearby austrian city, were determined. rabv shares only 75%-77% nucle ...200515752439
flaviviruses in europe: complex circulation patterns and their consequences for the diagnosis and control of west nile 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 ...201324225644
development of immunoglobulin m capture enzyme-linked immunosorbent assay to differentiate human flavivirus infections occurring in australia.we report the development of a flavivirus immunoglobulin m (igm) capture enzyme-linked immunosorbent assay (mac-elisa) which improves the determination of an infecting flavivirus serotype over that by current serological methods. a panel of 165 igm-positive sera from flavivirus patients with specific diagnostic results was tested by the flavivirus mac-elisa using a panel of 10 antigens. for 134 of these sera (81.2%), the highest reactivity was demonstrated against the infecting virus, which was ...200515753249
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 ...201019945487
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 ...200818218114
murray valley encephalitis in australia, 1974: antibody response in cases and community.fifty-three patients accepted on clinical grounds as cases of murray valley encephalitis (mve) in australia in 1974 were examined for antibody to mve virus. only one (who died early in the disease and whose diagnosis was confirmed by virus isolation) did not develop antibody; 13 patients showed stationary or single convalescent titres not diagnostic of recent infection, but other evidence that infection was recent was obtained in eight; 39 showed significant rise or fall in titre confirming rece ...19761071876
infection of western gray kangaroos (macropus fuliginosus) with australian arboviruses associated with human infection.more than 75 arboviruses (arthropod-borne viruses) have been identified in australia. while alfuy virus (alfv), barmah forest virus (bfv), edge hill virus (ehv), kokobera virus (kokv), murray valley encephalitis virus (mvev), sindbis virus (sinv), ross river virus (rrv), stratford virus (strv), and west nile virus strain kunjin (kunv) have been associated with human infection, there remains a paucity of data regarding their respective transmission cycles and any potential nonhuman vertebrate hos ...202031556842
feasibility of cross-protective vaccination against flaviviruses of the japanese encephalitis serocomplex.serological cross-reactivity providing cross-protective immunity between antigenically related viruses is a cornerstone of vaccination. it was the immunological basis for the first human vaccine against smallpox introduced more than 200 years ago, and continues to underpin modern vaccine development as has recently been shown for human papillomavirus vaccines, which confer cross-protection against other oncogenic papillomavirus types not present in the vaccine. here, we review the feasibility of ...022309667
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.025544857
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