Publications

culex torrentium mosquito role as major enzootic vector defined by rate of sindbis virus infection, sweden, 2009.	we isolated sindbis virus (sinv) from the enzootic mosquito vectors culex torrentium, cx. pipiens, and culiseta morsitans collected in an area of sweden where sinv disease is endemic. the infection rate in cx. torrentium mosquitoes was exceptionally high (36 infections/1,000 mosquitoes), defining cx. torrentium as the main enzootic vector of sinv in scandinavia.	0	25898013
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
not waiting for godot: proactive efforts to find potential zoonotic agents.		0	18717005
vector competence of culex neavei (diptera: culicidae) for usutu virus.	usutu virus (usuv), a flavivirus belonging to the japanese encephalitis serocomplex, was isolated for the first time from a culex neavei mosquito in 1959 in south africa. despite multiple isolations of usuv from cx. neavei in africa, its vector competence remains unproven. therefore, we infected cx. neavei orally with the usuv reference strain and used reverse transcription-polymerase chain reaction and an indirect immunofluorescence assay to detect virus in bodies, legs, wings, and saliva of mo ...	0	22665607
emerging and re-emerging viruses: a global challenge illustrated by chikungunya virus outbreaks.	in recent decades, the issue of emerging and re-emerging infectious diseases, especially those related to viruses, has become an increasingly important area of concern in public health. it is of significance to anticipate future epidemics by accumulating knowledge through appropriate research and by monitoring their emergence using indicators from different sources. the objective is to alert and respond effectively in order to reduce the adverse impact on the general populations. most of the eme ...	0	24175207
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
detection of west nile virus rna (lineages 1 and 2) in an external quality assessment programme for laboratories screening blood and blood components for west nile virus by nucleic acid amplification testing.	a second italian external quality assessment programme was run in 2011 to assess the performance of blood transfusion centres in detecting west nile virus rna in plasma.	0	23117401
usutu virus in bats, germany, 2013.		0	25271769
usutu virus in migratory song thrushes, spain.		0	23764143
flaviviruses in game birds, southern spain, 2011-2012.		0	23735195
putative lineage of novel african usutu virus, central europe.	we characterized the complete genome of a putative novel usutu virus (usuv) strain (usutu-bonn) detected in a dead blackbird from germany. genomic analysis revealed several unique amino acid substitutions among the polyprotein gene. phylogenetic analyses demonstrated that usutu-bonn constitutes a putative novel african usuv lineage, which was probably recently introduced to central europe.	0	26291923
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 ...	0	22309667
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
west nile virus: a re-emerging pathogen revisited.	west nile virus (wnv), a flavivirus of the flaviviridae family, is maintained in nature in an enzootic transmission cycle between avian hosts and ornithophilic mosquito vectors, although the virus occasionally infects other vertebrates. wnv causes sporadic disease outbreaks in horses and humans, which may result in febrile illness, meningitis, encephalitis and flaccid paralysis. until recently, its medical and veterinary health concern was relatively low; however, the number, frequency and sever ...	0	24175211
background review for diagnostic test development for zika virus infection.	to review the state of knowledge about diagnostic testing for zika virus infection and identify areas of research needed to address the current gaps in knowledge.	0	27516635
putative new west nile virus lineage in uranotaenia unguiculata mosquitoes, austria, 2013.	west nile virus (wnv) is becoming more widespread and markedly effecting public health. we sequenced the complete polyprotein gene of a divergent wnv strain newly detected in a pool of uranotaenia unguiculata mosquitoes in austria. phylogenetic analyses suggest that the new strain constitutes a ninth wnv lineage or a sublineage of wnv lineage 4.	0	25418009
dual emergence of usutu virus in common blackbirds, eastern france, 2015.		0	27869608
tick-borne encephalitis virus in horses, austria, 2011.	an unexpectedly high infection rate (26.1%) of tick-borne encephalitis virus (tbev) was identified in a herd of 257 horses of the same breed distributed among 3 federal states in austria. young age (p<0.001) and male sex (p=0.001) were positively associated with infection.	0	23631894
widespread usutu virus outbreak in birds in the netherlands, 2016.	we report a widespread usutu virus outbreak in birds in the netherlands. viral presence had been detected through targeted surveillance as early as april 2016 and increased mortality in common blackbirds and captive great grey owls was noticed from august 2016 onwards. usutu virus infection was confirmed by post-mortem examination and rt-pcr. extensive usutu virus activity in the netherlands in 2016 underlines the need to monitor mosquito activity and mosquito-borne infections in 2017 and beyond ...	0	27918257
usutu virus, italy, 1996.	retrospective analysis of archived tissue samples from bird deaths in the tuscany region of italy in 1996 identified usutu virus. partial sequencing confirmed identity with the 2001 vienna strain and provided evidence for a much earlier introduction of this virus into europe than previously assumed.	0	23347844
multidisciplinary and evidence-based method for prioritizing diseases of food-producing animals and zoonoses.	to prioritize 100 animal diseases and zoonoses in europe, we used a multicriteria decision-making procedure based on opinions of experts and evidence-based data. forty international experts performed intracategory and intercategory weighting of 57 prioritization criteria. two methods (deterministic with mean of each weight and probabilistic with distribution functions of weights by using monte carlo simulation) were used to calculate a score for each disease. consecutive ranking was established. ...	0	22469519
the isolation of west nile virus from man and of usutu virus from the bird-biting mosquito mansonia aurites (theobald) in the entebbe area of uganda.		1964	14212897
antigenic relationships among nigerian strains of west nile virus by complement fixation and agar gel precipitation techniques.	using two serological techniques, eight nigerian west nile virus isolates were investigated to determine antigenic relationships among them, and to find out if these virus isolates were related to west nile virus strains from the different zoogeographic areas of the world. one virus differed significantly from the seven other strains and was later found to be a strain of usutu virus. the remaining strains were differentiated into two serological intratypic groups depending on their cross reactio ...	1976	60810
antigenic analysis of nigerian strains of west nile virus by neutralization test.	employing neutralization tests, eight nigerian strains of west nile virus were investigated to determine antigenic relationships among them. one virus strain differed so significantly from the others and was later found to be a strain of usutu virus. the other seven strains were differentiated into two serological intratypic groups dependent on their cross reactions with two strains which served as prototypes for each group. it was found that for epidemiological studies, screening of sera and se ...	1976	16296127
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.	2002	11996693
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- ...	2002	12095429
serological evidence of west nile virus, usutu virus and sindbis virus infection of birds in the uk.	the introduction and rapid dispersal of the african flavivirus west nile virus (wnv) throughout north america, and the high fatality rate due to encephalitis in birds, horses, other wildlife species and humans, has attracted major attention worldwide. usutu virus, another flavivirus, came to prominence in 2001, when it was identified as the agent responsible for a drop in the bird population in austria; previously this encephalitic virus was found only in birds and mosquitoes in africa. sindbis ...	2003	13679615
usutu virus activity in austria, 2001-2002.	usutu virus (usuv), a member of the mosquito-borne clade within the flaviviridae family, was responsible for avian mortality in austria in 2001. in 2002, the virus continued to kill birds, predominantly blackbirds. high numbers of avian deaths were recorded within the city of vienna and in surrounding districts of the federal state of lower austria, while single die-offs were noticed in the federal states of styria and burgenland. a total of 72 birds were submitted for laboratory examination, 30 ...	2003	14554255
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 ...	2003	12584335
[usutu virus in austria reminds one of the west nile virus in the usa].		2004	15822217
complete genome analysis and molecular characterization of usutu virus that emerged in austria in 2001: comparison with the south african strain saar-1776 and other flaviviruses.	here we describe the complete genome sequences of two strains of usutu virus (usuv), a mosquito-borne member of the genus flavivirus in the japanese encephalitis virus (jev) serogroup. usuv was detected in austria in 2001 causing a high mortality rate in blackbirds; the reference strain (saar-1776) was isolated in 1958 from mosquitoes in south africa and has never been associated with avian mortality. the austrian and south african isolates exhibited 97% nucleotide and 99% amino acid identity. p ...	2004	15464850
experimental usutu virus infection of suckling mice causes neuronal and glial cell apoptosis and demyelination.	usutu virus (usuv), a mosquito-borne flavivirus of the japanese encephalitis virus group has been responsible for avian mortality in austria since 2001. in the present study, the neuropathogenicity and neuroinvasiveness of usuv for 1-week-old suckling mice was investigated. after intraperitoneal inoculation, clinical signs like depression, disorientation, paraplegia, paralysis and coma were observed between 6 and 11 days post infection. histologically, there was widespread neuronal apoptosis esp ...	2004	15372281
pathology and viral distribution in fatal usutu virus infections of birds from the 2001 and 2002 outbreaks in austria.	in the summer of 2001, usutu virus (usuv) was isolated for the first time in europe, from an episode of mass mortality in eurasian blackbirds (turdus merula). in the present study, 40 of the birds (representing three species), confirmed as cases of usuv infection, were examined by four methods (histopathology, immunohistochemistry [ihc], in-situ hybridization [ish] and reverse-transcriptase polymerase chain reaction [rt-pcr]). the major macroscopical finding was hepatosplenomegaly; histologicall ...	2004	15276857
in vitro host-cell susceptibility to usutu virus.	we investigated the susceptibility to usutu virus (flavivirus) of 13 permanent cell lines, 3 primary cell cultures, and chicken embryos. vero, pk-15, and goose embryo fibroblast cells developed cytopathic effects; however, viral multiplication was detected in all mammalian cell types by immunohistochemical tests. chicken embryo fibroblast cells and chicken embryos were resistant.	2005	15752450
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 ...	2005	15752439
limited pathogenicity of usutu virus for the domestic chicken (gallus domesticus).	in summer 2001, usutu virus (usuv), a mosquito-borne flavivirus, was isolated for the first time in europe during a mortality incident among eurasian blackbirds (turdus merula) in austria. chickens are frequently used as sentinel animals for arbovirus surveillance systems. in the present study, the pathogenicity of usuv for specific pathogen free chickens was investigated. ten 2-week-old chickens were inoculated intravenously with 0.1 ml inoculum containing 10(3) median (50%) tissue culture infe ...	2005	16236570
cleavage targets and the d-arginine-based inhibitors of the west nile virus ns3 processing proteinase.	mosquito-borne wnv (west nile virus) is an emerging global threat. the ns3 proteinase, which is essential for the proteolytic processing of the viral polyprotein precursor, is a promising drug target. we have isolated and biochemically characterized the recombinant, highly active ns3 proteinase. we have determined that the ns3 proteinase functions in a manner that is distantly similar to furin in cleaving the peptide and protein substrates. we determined that aprotinin and d-arginine-based 9-12- ...	2006	16229682
detection of seroconversion to west nile virus, usutu virus and sindbis virus in uk sentinel chickens.	we previously reported evidence of west nile virus (wnv) circulation in uk birds, probably introduced by migratory birds from overseas. we now demonstrate wnv-specific seroconversion in sentinel chickens raised on an english farm. maternal neutralizing antibodies to wnv in hatchlings declined within three weeks. during the following months, healthy chickens developed wnv neutralizing antibodies that were confirmed by immunoblotting and indirect immunofluorescence tests using wnv antigens. the pr ...	2006	16952307
serological evidence of west nile virus (wnv) in mammalian species in turkey.	in this study, the sera collected from a variety of mammalian species (ass-mules, cat, cattle, dog, horse, human and sheep) in 10 representative provinces of turkey, were surveyed for the presence of neutralizing antibodies to west nile virus (wnv). overall, 1 of 40 (2.5%) ass-mules, 4 of 100 (4%) cattle, 43 of 114 (37.7%) dogs, 35 of 259 (13.5%) horses, 18 of 88 (20.4%) humans and 1 of 100 (1%) sheep, tested positive for wnv-neutralizing antibodies. the results indicate that a wide range of mam ...	2006	16316496
limited pathogenicity of usutu virus for the domestic goose (anser anser f. domestica) following experimental inoculation.	usutu virus (usuv) is a mosquito-borne flavivirus of the japanese encephalitis virus group, which has been associated with avian mortality in austria since 2001. the affected birds are predominantly eurasian blackbirds (turdus merula). in the present study, the pathogenicity of usuv for domestic geese (anser anser f. domestica) was investigated. eleven 2-week-old geese were inoculated intramuscularly with 5 x 10(4) 50% tissue culture infectious dose of usuv strain vienna-2001 blackbird. no clini ...	2006	16629984
potential arbovirus emergence and implications for the united kingdom.	arboviruses have evolved a number of strategies to survive environmental challenges. this review examines the factors that may determine arbovirus emergence, provides examples of arboviruses that have emerged into new habitats, reviews the arbovirus situation in western europe in detail, discusses potential arthropod vectors, and attempts to predict the risk for arbovirus emergence in the united kingdom. we conclude that climate change is probably the most important requirement for the emergence ...	2006	16704800
lineage 1 and 2 strains of encephalitic west nile virus, central europe.	two different west nile virus (wnv) strains caused lethal encephalitis in a flock of geese and a goshawk in southeastern hungary in 2003 and 2004, respectively. during the outbreak in geese, 14 confirmed human cases of wnv encephalitis and meningitis were reported in the same area. sequencing of complete genomes of both wnv strains and phylogenetic analyses showed that the goose-derived strain exhibits closest genetic relationship to strains isolated in 1998 in israel and to the strain that emer ...	2006	16704810
monitoring of usutu virus activity and spread by using dead bird surveillance in austria, 2003-2005.	usutu virus has been causing avian mortality in austria since its emergence in 2001. between 2003 and 2005 a total of 504 dead birds were examined by reverse-transcriptase polymerase chain reaction and immunohistochemistry for the presence of usutu virus nucleic acid and antigen, respectively. in 2003, 92 birds (out of 177 birds) belonging to five different species were positive, while in 2004, only 11 (of 224) birds, and in 2005, 4 (of 103) birds proved positive, all of which were blackbirds (t ...	2007	17346908
west nile virus circulation detected in northern italy in sentinel chickens.	ninety percent (56/62) of sentinel chickens introduced to two regions within the italian alps seroconverted to west nile virus (wnv) during the summer of 2005, showing a range of antibody titres from 1/20 to 1/320 in a virus neutralization test. neutralization specificity for wnv antibodies was confirmed on an additional 34 sera that were tested in parallel against wnv (16/34 seropositivity), usutu virus (3/34 seropositivity) and koutango virus. the geometric mean neutralizing titre (gmt) calcul ...	2007	17767411
seroconversion in wild birds and local circulation of west nile virus, spain.	a serosurvey for neutralizing antibodies against west nile virus (wnv) in common coots (fulica atra) was conducted in doñana, spain. antibody prevalence was highest in 2003, intermediate in 2004, and lowest in 2005. some birds seroreverted <1 year after first capture. seroconversion of birds suggests local circulation of the virus.	2007	18258046
emergence of usutu virus in hungary.	in 2001, usutu virus (usuv), a mosquito-borne flavivirus of the japanese encephalitis virus serogroup related to west nile virus and previously restricted to sub-saharan africa, emerged in wild and zoo birds in and around vienna, austria. in order to monitor the spread of the infection, a dead bird surveillance program was established in austria and in neighboring hungary. in hungary, 332 dead birds belonging to 52 species were tested for usuv infection between 2003 and 2006. in the first 2 year ...	2007	17913929
serologic evidence of west nile virus infections in wild birds captured in germany.	to assess the risk of acquiring a west nile virus (wnv) infection in germany, we investigated samples from migrating and from resident birds. because of their stay in or migration through wnv-endemic regions, these birds are at risk to become infected with wnv. blood samples from 3,399 birds, representing 87 bird species, were collected in germany in 2000 and in 2002-2005. overall, 53 birds belonging to 5 species had wnv-neutralizing antibodies. fifty-nine birds belonging to 9 species were react ...	2007	17690413
structural bases for substrate recognition and activity in meaban virus nucleoside-2'-o-methyltransferase.	viral methyltransferases are involved in the mrna capping process, resulting in the transfer of a methyl group from s-adenosyl-l-methionine to capped rna. two groups of methyltransferases (mtases) are known: (guanine-n7)-methyltransferases (n7mtases), adding a methyl group onto the n7 atom of guanine, and (nucleoside-2'-o-)-methyltransferases (2'omtases), adding a methyl group to a ribose hydroxyl. we have expressed and purified two constructs of meaban virus (mv; genus flavivirus) ns5 protein m ...	2007	17473012
development of multiplex real-time reverse transcriptase pcr assays for detecting eight medically important flaviviruses in mosquitoes.	a multiplex real-time reverse transcriptase pcr has been developed for the rapid detection and identification of eight medically important flaviviruses from laboratory-reared, virus-infected mosquito pools. the method used involves the gene-specific amplification of yellow fever virus (yfv), japanese encephalitis virus (jev), west nile virus (wnv), st. louis encephalitis virus (slev), and dengue virus (denv) serotypes 1 to 4 (denv-1 to denv-4, respectively) by use of the flavivirus consensus amp ...	2007	17108075
possible ecology and epidemiology of medically important mosquito-borne arboviruses in great britain.	nine different arboviruses are known to be transmitted by, or associated with, mosquitoes in europe, and several (west nile, sindbis and tahyna viruses) are reported to cause outbreaks of human disease. although there have been no reported human cases in great britain (gb), there have been no published in-depth serological surveys for evidence of human infection. this paper investigates the ecological and entomological factors that could influence or restrict transmission of these viruses in gb, ...	2007	16893487
bioterrorism or natural disasters: what shall we worry about next?		2007	17696315
serological evidence of continuing high usutu virus (flaviviridae) activity and establishment of herd immunity in wild birds in austria.	usutu virus (usuv), family flaviviridae, has been responsible for avian mortality in austria from 2001 to 2006. the proportion of usuv-positive individuals among the investigated dead birds decreased dramatically after 2004. to test the hypothesis that establishment of herd immunity might be responsible, serological examinations of susceptible wild birds were performed. blood samples of 442 wild birds of 55 species were collected in 4 consecutive years (2003--2006). in addition, 86 individuals f ...	2008	17869454
serological evidence of usutu virus occurrence in north-eastern italy.	in the recent years, usutu virus (usuv), a flavivirus of the japanese encephalitis virus complex, has been reported in central europe. as part of a systematic surveillance programme to monitor possible entrance and/or circulation of vector-borne viruses, since 2001, sentinel-chicken flocks were placed throughout the italian territory nearby areas considered at risk of virus introduction. they have been periodically checked for the presence of antibodies against flaviviruses by indirect elisa, pl ...	2008	18667029
serologic survey of birds for west nile flavivirus in southern moravia (czech republic).	a serosurvey for west nile virus (wnv) was carried out in 54 domestic birds (geese and ducks bred on fishponds) and 391 wild birds representing 28 migratory and resident species, using a plaque-reduction neutralization microtest with vero cells and egyptian topotype eg-101 strain as test virus. the birds were sampled in the south-moravian fishpond ecosystem between 2004 and 2006. antibodies to wnv were not detected in domestic waterfowl, but 23 (5.9%) free-living birds of 10 species showed a pos ...	2008	18454599
explaining usutu virus dynamics in austria: model development and calibration.	usutu virus (usuv), a flavivirus of the japanese encephalitis virus complex, was for the first time detected outside africa in the region around vienna (austria) in 2001 by weissenböck et al. [weissenböck, h., kolodziejek, j., url, a., lussy, h., rebel-bauder, b., nowotny, n., 2002. emergence of usutu virus, an african mosquito-borne flavivirus of the japanese encephalitis virus group, central europe. emerg. infect. dis. 8, 652-656]. usuv is an arthropod-borne virus (arbovirus) circulating betwe ...	2008	18314208
west nile virus in golden eagles, spain, 2007.		2008	18760030
sindbis virus infection in resident birds, migratory birds, and humans, finland.	sindbis virus (sinv), a mosquito-borne virus that causes rash and arthritis, has been causing outbreaks in humans every seventh year in northern europe. to gain a better understanding of sinv epidemiology in finland, we searched for sinv antibodies in 621 resident grouse, whose population declines have coincided with human sinv outbreaks, and in 836 migratory birds. we used hemagglutination-inhibition and neutralization tests for the bird samples and enzyme immunoassays and hemagglutination-inhi ...	2008	18258075
orthomyxo-, paramyxo- and flavivirus infections in wild waterfowl in finland.	screening wild birds for viral pathogens has become increasingly important. we tested a screening approach based on blood and cloacal and tracheal swabs collected by hunters to study the prevalence of influenza a, paramyxo-, flavi-, and alphaviruses in finnish wild waterfowl, which has been previously unknown. we studied 310 blood samples and 115 mixed tracheal and cloacal swabs collected from hunted waterfowl in 2006. samples were screened by rt-pcr and serologically by hemagglutination inhibit ...	2008	18307758
usutu virus sequences in culex pipiens (diptera: culicidae), spain.		2008	18439389
fundamental issues in mosquito surveillance for arboviral transmission.	marked spatiotemporal variabilities in mosquito infection of arboviruses, exemplified by the transmission of west nile virus (wnv) in america, require adaptive strategies for mosquito sampling, pool screening and data analyses. currently there is a lack of reliable and consistent measures of risk exposure, which may compromise comparison of surveillance data. based on quantitative reasoning, we critically examined fundamental issues regarding mosquito sampling design and estimation of transmissi ...	2008	18466940
use of sentinel chickens to study the transmission dynamics of west nile virus in a sahelian ecosystem.	during the 2003 rainy season, a follow-up survey in sentinel chickens was undertaken to assess the seasonal transmission of west nile virus (wnv) in a sahelian ecosystem: the ferlo (senegal). the estimated incidence rate in chickens was 14% (95% ci 7-29), with a very low level of transmission between july and september, and a transmission peak occurring between september and october. comparing these results with the estimate obtained from a previous transversal serological study performed on hor ...	2008	17559695
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
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
theoretical study of the usutu virus helicase 3d structure, by means of computer-aided homology modelling.	background: usutu virus belongs to the flaviviridae viral family and constitutes an important pathogen. the viral helicase is an ideal target for inhibitor design, since this enzyme is essential for the survival, proliferation and transmission of the virus. results: towards a drug-design approach, the 3d model of the usutu virus helicase structure has been designed, using conventional homology modelling techniques and the known 3d-structure of the murray valley encephalitis virus helicase, of th ...	2009	19555498
simulation of climate-change scenarios to explain usutu-virus dynamics in austria.	the emergence and spread of infectious diseases in mid-latitudes, so far mainly observed in the tropics, considerably increase under the current situation of climate change. a recent example is the usutu virus (usuv) outbreak in austria. usuv is closely related to the west nile virus in the u.s. and caused mass mortalities mainly of blackbirds (turdus merula). the usuv flavivirus persists in a natural transmission cycle between vectors (mosquitoes) and host reservoirs (birds) and leads - once en ...	2009	18715663
west nile virus antibodies in wild birds, morocco, 2008.	to determine circulation of west nile virus (wnv) during nonepidemic times, we serosurveyed wild birds of morocco in 2008. we found antibodies against wnv in 12 (3.5%) birds, against usutu virus in 1 (0.3%), and against both in 2 (0.6%). high wnv prevalence among juvenile birds suggests local virus circulation among resident birds.	2009	19861065
usutu virus infection in a patient who underwent orthotropic liver transplantation, italy, august-september 2009.	we report a case of usutu virus (usuv)-related illness in a patient that underwent an orthotropic liver transplant (olt). post transplant, the patient developed clinical signs of a possible neuroinvasive disease with a significant loss of cerebral functions. usuv was isolated in vero e6 cells from a plasma sample obtained immediately before the surgery, and usuv rna was demonstrated by rt-pcr and sequencing. this report enlarges the panel of emerging mosquito-borne flavivirus-related disease in ...	2009	20070935
first human case of usutu virus neuroinvasive infection, italy, august-september 2009.	we report the first worldwide case of usutu virus (usuv) neuroinvasive infection in a patient with diffuse large b cell lymphoma who presented with fever and neurological symptoms and was diagnosed with meningoencephalitits. the cerebrospinal fluid was positive for usuv, and usuv was also demonstrated in serum and plasma samples by rt-pcr and sequencing. partial sequences of the premembrane and ns5 regions of the viral genome were similar to the usuv vienna and budapest isolates.	2009	20070936
impact of climate change and other factors on emerging arbovirus diseases.	while some skeptics remain unconvinced that global climate change is a reality, there is no doubt that during the past 50 years or so, patterns of emerging arbovirus diseases have changed significantly. can this be attributed to climate change? climate is a major factor in determining: (1) the geographic and temporal distribution of arthropods; (2) characteristics of arthropod life cycles; (3) dispersal patterns of associated arboviruses; (4) the evolution of arboviruses; and (5) the efficiency ...	2009	18799177
a conserved predicted pseudoknot in the ns2a-encoding sequence of west nile and japanese encephalitis flaviviruses suggests ns1' may derive from ribosomal frameshifting.	japanese encephalitis, west nile, usutu and murray valley encephalitis viruses form a tight subgroup within the larger flavivirus genus. these viruses utilize a single-polyprotein expression strategy, resulting in ~10 mature proteins. plotting the conservation at synonymous sites along the polyprotein coding sequence reveals strong conservation peaks at the very 5' end of the coding sequence, and also at the 5' end of the sequence encoding the ns2a protein. such peaks are generally indicative of ...	2009	19196463
the zoonotic flaviviruses of southern, south-eastern and eastern asia, and australasia: the potential for emergent viruses.	the genus flaviviridae comprises about 70 members, of which about 30 are found in southern, south-eastern and eastern asia and australasia. these include major pathogens such as japanese encephalitis (je), west nile (wn), murray valley encephalitis (mve), tick-borne encephalitis, kyasanur forest disease virus, and the dengue viruses. other members are known to be associated with mild febrile disease in humans, or with no known disease. in addition, novel flaviviruses continue to be discovered, a ...	2009	19486319
characterization of a novel flavivirus from mosquitoes in northern europe that is related to mosquito-borne flaviviruses of the tropics.	a novel flavivirus was isolated from mosquitoes in finland, representing the first mosquito-borne flavivirus from northern europe. the isolate, designated lammi virus (lamv), was antigenically cross-reactive with other flaviviruses and exhibited typical flavivirus morphology as determined by electron microscopy. the genomic sequence of lamv was highly divergent from the recognized flaviviruses, and yet the polyprotein properties resembled those of mosquito-borne flaviviruses. phylogenetic analys ...	2009	19570865
zoonotic mosquito-borne flaviviruses: worldwide presence of agents with proven pathogenicity and potential candidates of future emerging diseases.	an update on the mosquito-borne flavivirus species including certain subtypes, as listed in the eighth report of the international committee on taxonomy of viruses, is given. special emphasis is placed on viruses which have been shown to cause diseases in animals, and viruses for which no pathogenicity has been proven yet. several recent examples (usutu virus and lineage-2 west nile virus in central europe, zika virus in micronesia) have shown that sources providing information on such scientifi ...	2010	19762169
usutu virus in wild birds in northern italy.	usutu virus (usuv) infection was diagnosed in two free-living blackbirds and in three captive owls belonging to two different species in northern italy in the summers of 2006-2008. diagnosis was established by immunohistochemistry and rt-pcr. rt-pcr was performed on frozen and on paraffin-embedded tissues (pet), respectively. from the frozen samples a partial sequence of the putative usuv e and ns1 proteins (1229 bp) was determined, whereas partial sequences of the putative ns3 (278 bp) and ns5 ...	2010	19720475
insights into arbovirus evolution and adaptation from experimental studies.	arthropod-borne viruses (arboviruses) are maintained in nature by cycling between vertebrate hosts and haematophagous invertebrate vectors. these viruses are responsible for causing a significant public health burden throughout the world, with over 100 species having the capacity to cause human disease. arbovirus outbreaks in previously naïve environments demonstrate the potential of these pathogens for expansion and emergence, possibly exacerbated more recently by changing climates. these recen ...	2010	21994633
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
west nile virus and its emergence in the united states of america.	zoonotic west nile virus (wnv) circulates in natural transmission cycles involving certain mosquitoes and birds, horses, humans, and a range of other vertebrates are incidental hosts. clinical infections in humans can range in severity from uncomplicated wnv fever to fatal meningoencephalitis. since its introduction to the western hemisphere in 1999, wnv had spread across north america, central and south america and the caribbean, although the vast majority of severe human cases have occurred in ...	2010	21188801
putative new lineage of west nile virus, spain.	to ascertain the presence of west nile virus (wnv), we sampled mosquitoes in 2006 in locations in southern spain where humans had been infected. wnv genomic rna was detected in 1 pool from unfed female culex pipiens mosquitoes. phylogenetic analysis demonstrated that this sequence cannot be assigned to previously described lineages of wnv.	2010	20202444
emergence of zoonotic arboviruses by animal trade and migration.	abstract: arboviruses are transmitted in nature exclusively or to a major extend by arthropods. they belong to the most important viruses invading new areas in the world and their occurrence is strongly influenced by climatic changes due to the life cycle of the transmitting vectors. several arboviruses have emerged in new regions of the world during the last years, like west nile virus (wnv) in the americas, usutu virus (usuv) in central europe, or rift valley fever virus (rvfv) in the arabian ...	2010	20377873
design and validation of an oligonucleotide probe for the detection of protozoa from the order trichomonadida using chromogenic in situ hybridization.	infections with protozoal parasites of the order trichomonadida are often observed in veterinary medicine. based on the trichomonad species involved these infections are either asymptomatic or can lead to sometimes serious disease. to further study protozoal agents of the order trichomonadida the establishment of a method to detect trichomonads directly in the tissue, allowing parasite-lesion correlation, is necessary. here we describe the design and evaluation of an oligonucleotide probe for ch ...	2010	20395049
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
inhibition of enveloped virus infection of cultured cells by valproic acid.	valproic acid (vpa) is a short-chain fatty acid commonly used for treatment of neurological disorders. as vpa can interfere with cellular lipid metabolism, its effect on the infection of cultured cells by viruses of seven viral families relevant to human and animal health, including eight enveloped and four nonenveloped viruses, was analyzed. vpa drastically inhibited multiplication of all the enveloped viruses tested, including the zoonotic lymphocytic choriomeningitis virus and west nile virus ...	2010	21106740
ecological approaches to informing public health policy and risk assessments on emerging vector-borne zoonoses.	pathogens associated with vector-borne zoonoses occur in enzootic cycles within nature. they are driven by a combination of vertebrate host and invertebrate vector population dynamics, which in turn respond to changes in environmental stimuli. human involvement in these cycles, and hence the occurrence of human disease, is often to act as incidental host. from a public health perspective our ability to better predict human outbreaks of these diseases and prepare intervention and mitigation strat ...	2010	22460391
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. ...	2010	21159871
arboviral encephalitides: transmission, emergence, and pathogenesis.	arthropod-borne viruses (arboviruses) are of paramount concern as a group of pathogens at the forefront of emerging and re-emerging diseases. although some arboviral infections are asymptomatic or present with a mild influenza-like illness, many are important human and veterinary pathogens causing serious illness ranging from rash and arthritis to encephalitis and hemorrhagic fever. here, we discuss arboviruses from diverse families (flaviviruses, alphaviruses, and the bunyaviridae) that are cau ...	2010	20652430
[current status and eco-epidemiology of mosquito-borne arboviruses (diptera: culicidae) in spain].	in this manuscript we analize the possible emergence and/or re-emergence in spain of some of the mosquito-borne arboviruses (diptera: culicidae) with highest incidence in recent years. the faunistic, bioecological and distributional data of the culicids in our country allow to differentiate between species with ability to maintain the enzootic cycles of arboviruses from others that can act as bridge vectors to the human population. the results show the existence of several common and anthropophi ...	2010	20661525
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
emerging infectious disease leads to rapid population declines of common british birds.	emerging infectious diseases are increasingly cited as threats to wildlife, livestock and humans alike. they can threaten geographically isolated or critically endangered wildlife populations; however, relatively few studies have clearly demonstrated the extent to which emerging diseases can impact populations of common wildlife species. here, we report the impact of an emerging protozoal disease on british populations of greenfinch carduelis chloris and chaffinch fringilla coelebs, two of the m ...	2010	20805869
assessment of a novel real-time pan-flavivirus rt-polymerase chain reaction.	outbreaks of west nile virus (wnv) have occurred intermittently in regions around the mediterranean coast, and the virus may have become established in northern italy and romania, with reported intermittent outbreaks in spain, hungary, and france. wnv has also spread rapidly throughout the americas since its introduction into new york in 1999. this capacity to emerge in new geographical locations and to spread rapidly together with the current increase in incidence of other flaviviruses such as ...	2010	20854019
emergence and establishment of usutu virus infection in wild and captive avian species in and around zurich, switzerland--genomic and pathologic comparison to other central european outbreaks.	in late summer 2006 considerable mortality in wild and captive passeriformes and strigiformes was observed in zurich, switzerland. all animals were found in a range of 2 km(2). observed clinical signs involved depression, ruffled plumage, incoordination, seizures and peracute death. nutritional status was generally moderate to poor in wild birds, and variable in captive animals. necropsy showed marked splenomegaly, a mild hepatomegaly, and pulmonary hyperemia in most animals. histopathologic les ...	2010	20980109
false-positive transcription-mediated amplification assay detection of west nile virus in blood from a patient with viremia caused by an usutu virus infection.	detection of west nile virus (wnv) by nucleic acid amplification technology (naat) is used widely to screen blood and organ donations in areas where wnv is endemic. we report a false-positive result of a wnv transcription-mediated amplification assay (tma) in a patient with viremia that was caused by usutu virus, a mosquito-borne flavivirus.	2010	20592138
a rapid and specific real-time rt-pcr assay to identify usutu virus in human plasma, serum, and cerebrospinal fluid.	usutu virus (usuv), a flavivirus that belongs to the japanese encephalitis virus (jev) family, has recently emerged as a human pathogen, necessitating new diagnostic tools.	2010	21156352
first serological evidence of west nile virus activity in horses in serbia.	abstract west nile virus (wnv), the most widely distributed flavivirus worldwide, has lately reemerged in europe, causing worrisome outbreaks in humans and horses. serological analysis by enzyme-linked immunoassay and plaque reduction neutralization test showed for the first time in serbia that 12% of 349 horses presented specific neutralizing wnv antibodies, which in one case also cross-neutralized usutu virus (usuv). this is the first time that anti-usuv high neutralizing antibody titers are r ...	2011	21438694
duck egg-drop syndrome caused by byd virus, a new tembusu-related flavivirus.	since april 2010, a severe outbreak of duck viral infection, with egg drop, feed uptake decline and ovary-oviduct disease, has spread around the major duck-producing regions in china. a new virus, named byd virus, was isolated in different areas, and a similar disease was reproduced in healthy egg-producing ducks, infecting with the isolated virus. the virus was re-isolated from the affected ducks and replicated well in primary duck embryo fibroblasts and vero cells, causing the cytopathic effec ...	2011	21455312
usutu virus in italy: an emergence or a silent infection?	a two year study (2008-2009) was carried out to monitor the usutu virus (usuv) circulation in italy. sentinel horses and chickens, wild birds and mosquitoes were sampled and tested for the presence of usuv and usuv antibodies within the wnd national surveillance plan. seroconversion evidenced in sentinel animals proved that in these two years the virus has circulated in tuscany, emilia romagna, veneto and friuli venezia giulia regions. in veneto usuv caused a severe blackbird die-off disease inv ...	2011	21550731
usutu virus in africa.	abstract usutu virus (usuv) was discovered in south africa in 1959. since then, it has been reported in several african countries including senegal, central african republic, nigeria, uganda, burkina faso, cote d'ivoire, and morocco. in 2001, usuv has been identified for the first time outside of africa, namely in europe, where it caused a significant mortality among blackbirds in vienna, austria. in 2009, the first two human cases of usuv infection in europe have been reported in italy, causing ...	2011	21767160
west nile and usutu viruses in mosquitoes in spain, 2008-2009.	west nile virus lineage 1 (similar to the strains obtained from golden eagles in spain, 2007) and usutu virus (similar to the strains obtained from culex pipiens in spain, 2006) were detected in pools from culex perexiguus collected in southern spain in 2008 and 2009, respectively. this is the first detection and isolation of west nile virus lineage 1 from mosquitoes in spain.	2011	21734145
west nile virus replication requires fatty acid synthesis but is independent on phosphatidylinositol-4-phosphate lipids.	west nile virus (wnv) is a neurovirulent mosquito-borne flavivirus, which main natural hosts are birds but it also infects equines and humans, among other mammals. as in the case of other plus-stranded rna viruses, wnv replication is associated to intracellular membrane rearrangements. based on results obtained with a variety of viruses, different cellular processes have been shown to play important roles on these membrane rearrangements for efficient viral replication. as these processes are re ...	2011	21949814
Usutu virus: potential risk of human disease in Europe.	Usutu virus (USUV) is an African mosquito-borne flavivirus, member of the Japanese encephalitis antigenic group. This avian virus is transmitted by arthropod vectors (mainly mosquitoes of the Culex pipiens complex). It is well known that free-living birds, including migratory species, have the potential to disperse certain pathogenic microorganisms. Usutu virus has recently been introduced to Europe and is spreading through Austria, Hungary, Italy, Spain and Switzerland, causing disease in birds ...	2011	21871214
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.	2011	22000358