| attenuation of murray valley encephalitis virus by site-directed mutagenesis of the hinge and putative receptor-binding regions of the envelope protein. | molecular determinants of virulence in flaviviruses cluster in two regions on the three-dimensional structure of the envelope (e) protein; the base of domain ii, believed to serve as a hinge during ph-dependent conformational change in the endosome, and the lateral face of domain iii, which contains an integrin-binding motif arg-gly-asp (rgd) in mosquito-borne flaviviruses and is believed to form the receptor-binding site of the protein. in an effort to better understand the nature of attenuatio ... | 2001 | 11462041 |
| pathologic and immunohistochemical findings in naturally occuring west nile virus infection in horses. | the pathologic and peroxidase immunohistochemical features of west nile flavivirus (wnv) infection were compared in four horses from the northeastern united states and six horses from central italy. in all 10 animals, there were mild to severe polioencephalomyelitis with small t lymphocyte and lesser macrophage perivascular infiltrate, multifocal glial nodules, neutrophils, and occasional neuronophagia. perivascular hemorrhages, also noted macroscopically in two animals, were observed in 50% of ... | 2001 | 11467475 |
| western nile virus: a new public health concern. | in august 1999, the western hemisphere was introduced to the western nile virus for the first time in recorded history. many states have implemented screening and identification protocols for this previously rare virus. western nile virus (wnv) is a member of the flaviviridae family and it is transmitted by the culex pipiens mosquito, although other mosquito species have also been implicated in carrying the virus. human infection with west nile virus can range from asymptomatic to full blown enc ... | 2001 | 11471465 |
| west virginia department of health and human resources information for physicians--west nile virus. | | 2001 | 11471468 |
| ochlerotatus j. japonicus in frederick county, maryland: discovery, distribution, and vector competence for west nile virus. | ochlerotatus japonicus japonicus is reported for the 1st time south of the mason-dixon line, in frederick county, maryland. fifty-seven oviposition trap samples were collected throughout the county between june 30 and august 24, 2000. from 971 larvae reared from the oviposition traps, 5 species were identified: ochlerotatus triseriatus (45%), oc. j. japonicus (43%), aedes albopictus (7%), culex pipiens (4%), and toxorynchites ritulus septentrionalis (<1%). ochlerotatus j. japonicus was found wid ... | 2001 | 11480822 |
| west nile virus: new jersey's 2000 experience and surveillance plans for 2001. | | 2001 | 11481936 |
| west nile virus 2000-2001. | | 2001 | 11481943 |
| west nile virus: a newly emergent epidemic disease. | | 2001 | 11485653 |
| intercontinental transmission of west nile virus by migrating white storks. | | 2001 | 11485657 |
| st. louis encephalitis and west nile virus encephalitis. | st. louis encephalitis virus is a major cause of epidemic arboviral encephalitis in the us. transmitted by a mosquito vector, this virus is an annual public health concern during the late summer and early fall in much of the midwest and southeast. the characteristic epidemic features of this viral encephalitis coupled with public health surveillance and vector monitoring programs have made the diagnosis readily accessible during the past decade. recently, however, the arboviral landscape in the ... | 2001 | 11487457 |
| west nile virus. | | 2001 | 11495600 |
| epidemic west nile encephalitis, new york, 1999: results of a household-based seroepidemiological survey. | in the summer of 1999, west nile virus was recognised in the western hemisphere for the first time when it caused an epidemic of encephalitis and meningitis in the metropolitan area of new york city, ny, usa. intensive hospital-based surveillance identified 59 cases, including seven deaths in the region. we did a household-based seroepidemiological survey to assess more clearly the public-health impact of the epidemic, its range of illness, and risk factors associated with infection. | 2001 | 11498211 |
| to deet or not to deet? | | 2001 | 11499224 |
| the 3' stem loop of the west nile virus genomic rna can suppress translation of chimeric mrnas. | cis-acting elements that regulate translation have been identified in the 3' noncoding regions (ncrs) of cellular and viral mrnas. as one means of analyzing the effect on translation of the conserved 3' terminal rna structure of the west nile virus (wnv) genome, the translation efficiencies of chimeric mrnas composed of a cat reporter gene flanked by viral or nonviral 5' and 3' terminal sequences were compared. in vitro, the wnv 3'(+) stem loop (sl) rna reduced the translation efficiencies of ch ... | 2001 | 11504541 |
| west nile virus spreading. | | 2001 | 11505956 |
| emerging infectious pathogens of wildlife. | the first part of this paper surveys emerging pathogens of wildlife recorded on the promed web site for a 2-year period between 1998 and 2000. the majority of pathogens recorded as causing disease outbreaks in wildlife were viral in origin. anthropogenic activities caused the outbreaks in a significant majority of cases. the second part of the paper develops some matrix models for quantifying the basic reproductive number, r(0), for a variety of potential types of emergent pathogen that cause ou ... | 2001 | 11516378 |
| yellow fever vector live-virus vaccines: west nile virus vaccine development. | by combining molecular-biological techniques with our increased understanding of the effect of gene sequence modification on viral function, yellow fever 17d, a positive-strand rna virus vaccine, has been manipulated to induce a protective immune response against viruses of the same family (e.g. japanese encephalitis and dengue viruses). triggered by the emergence of west nile virus infections in the new world afflicting humans, horses and birds, the success of this recombinant technology has pr ... | 2001 | 11516995 |
| effects of microcosm scaling and food resources on growth and survival of larval culex pipiens. | we used a simple experimental design to test for the effects of microcosm scaling on the growth and survival of the mosquito, culex pipiens. microcosm and mesocosm studies are commonly used in ecology, and there is often an assumption that scaling doesn't affect experimental outcomes. the assumption is implicit in the design; choice of mesocosms may be arbitrary or based on convenience or cost. we tested the hypothesis that scale would influence larvae due to depth and surface area effects. larv ... | 2001 | 11527507 |
| from the centers for disease control and prevention. west nile virus activity--eastern united states, 2001. | | 2001 | 11529241 |
| quebec clears way for use of aerial pesticides to combat west nile virus. | | 2001 | 11531060 |
| dengue and other emerging flaviviruses. | flaviviruses are among the most important emerging viruses known to man. most are arboviruses (arthropod-borne) being transmitted by mosquitoes or ticks. they derived from a common ancestor 10-20000 years ago and are evolving rapidly to fill new ecological niches. many are spreading to new geographical areas and causing increased numbers of infections. traditionally, three clinical syndromes are recognized: fever-arthralgia-rash, viral haemorrhagic fever, and neurological disease, though for som ... | 2001 | 11531316 |
| additive effects characterize the interaction of antibodies involved in neutralization of the primary dualtropic human immunodeficiency virus type 1 isolate 89.6. | human immunodeficiency virus-type i (hiv-1) infection elicits antibodies (abs) directed against several regions of the gp120 and gp41 envelope glycoproteins. many of these abs are able to neutralize t-cell-line-adapted strains (tcla) of hiv-1, but only a few effectively neutralize primary hiv-1 isolates. the nature of hiv-1 neutralization has been carefully studied using human monoclonal abs (mabs), and the ability of such mabs to act in synergy to neutralize hiv-1 has also been extensively stud ... | 2001 | 11533181 |
| [many faces of west nile fever--the first case of west nile fever in the western galilee, israel]. | west nile fever (wnf) is caused by a b arbovirus, which was first isolated in 1937 in uganda. in israel the disease bears an epidemic character, and during 1950-1957 several widespread outbreaks of wnf were described in detail. it emerged from obscurity in 1999 when the first incursion of the virus in north america caused 62 cases of encephalitis and 7 deaths in new york. in 1996 an outbreak in romania signaled that wnf had emerged as clinically important disease in europe. the virus is transmit ... | 2001 | 11547466 |
| [west nile fever in israel--past and present]. | the present outbreak of west nile fever in israel, which started in july 2000, caused some amount of panic among the israeli public and interest among the medical, environmental and veterinary professions. the authors review the relevant literature and demonstrate that this disease has been recorded in the last 50 years in israel and is highly endemic in this country. the last outbreak in the late summer and autumn of the year 2000 was unique in its size: 429 serological proved cases and 29 deat ... | 2001 | 11547476 |
| induction of potent th1-type immune responses from a novel dna vaccine for west nile virus new york isolate (wnv-ny1999). | west nile virus (wnv) is a vectorborne pathogen that induces brain inflammation and death. recently, confirmed cases of infection and deaths have occurred in the united states mid-atlantic region. in this study, a dna vaccine encoding the wnv capsid protein was constructed, and the in vivo immune responses generated were investigated in dna vaccine-immunized mice. antigen-specific humoral and cellular immune responses were observed, including a potent induction of antigen-specific th1 and cytoto ... | 2001 | 11550123 |
| mutagenesis of the dengue virus type 2 ns3 protein within and outside helicase motifs: effects on enzyme activity and virus replication. | the protein ns3 of dengue virus type 2 (den-2) is the second largest nonstructural protein specified by the virus and is known to possess multiple enzymatic activities, including a serine proteinase located in the n-terminal region and an ntpase-helicase in the remaining 70% of the protein. the latter region has seven conserved helicase motifs found in all members of the family flaviviridae. den-2 ns3 lacking the proteinase region was synthesized as a fusion protein with glutathione s-transferas ... | 2001 | 11559795 |
| interleukin-1beta but not tumor necrosis factor is involved in west nile virus-induced langerhans cell migration from the skin in c57bl/6 mice. | langerhans cells are bone marrow-derived epidermal dendritic cells. they migrate out of the epidermis into the lymphatics and travel to the draining lymph nodes where they are responsible for the activation of t cells in the primary immune response. tumor necrosis factor and interleukin-1beta, have previously been shown to be responsible for langerhans cell migration in response to contact sensitizers in balb/c mice; however, which cytokines are responsible for mediating langerhans cell migratio ... | 2001 | 11564180 |
| west nile virus surveillance in romania: 1997-2000. | in response to the 1996 west nile (wn) fever epidemic that occurred in bucharest and southeastern romania, a surveillance program was established. the surveillance system detected 39 clinical human wn fever cases during the period 1997-2000: 14 cases in 1997, 5 cases in 1998, 7 cases in 1999, and 13 cases in 2000. thirty-eight of the 39 case-patients lived in the greater danube valley of southern romania, and 1 case-patient resided in the district of vaslui, located on the moldavian plateau. the ... | 2001 | 11572635 |
| flow cytometry compared with indirect immunofluorescence for rapid detection of dengue virus type 1 after amplification in tissue culture. | dengue virus (dv) was detected early in infected mosquito c6/36 cells by using indirect immunofluorescence (if) in conjunction with flow cytometry. three fixation-permeabilization methods and three dv serotype 1 (den-1)-specific monoclonal antibodies, 8-8 (anti-e), 16-4 (anti-ns1), and 15f3-1 (anti-ns1), were evaluated for the detection of den-1 in infected c6/36 cells. we found that these three monoclonal antibodies were capable of detecting dv in c6/36 cells as early as 24 h postinoculation by ... | 2001 | 11574589 |
| transcriptional regulation of major histocompatibility complex class i by flavivirus west nile is dependent on nf-kappab activation. | infection by the flavivirus west nile (wnv) is associated with a virus-specific increase of major histocompatibility complex class i (mhc-i) molecules on the cell surface of diploid vertebrate cells. the increased mhc-i cell surface expression is functional and is associated with increased susceptibility to secondary wnv-immune and alloimmune cytotoxic t cells. wnv-induced up-regulation of cell surface mhc-i expression is associated with nf-kappab activation and increased transcription of mhc-i ... | 2001 | 11574908 |
| ribavirin--current status of a broad spectrum antiviral agent. | ribavirin is a very broad-spectrum virustatic antiviral agent, first synthesised in 1972. it is characterised by low toxicity apart from reversible anaemia, usually mild. its multiple mechanisms of action mean that viral resistance rarely develops. it can be administered orally, intravenously, or via a nebuliser. it has shown varying degrees of clinical efficacy in a variety of human diseases including respiratory tract infections due to respiratory syncytial virus and influenza, measles, herpes ... | 2001 | 11585000 |
| west nile virus: a reemerging global pathogen. | | 2001 | 11585520 |
| crow deaths as a sentinel surveillance system for west nile virus in the northeastern united states, 1999. | in addition to human encephalitis and meningitis cases, the west nile (wn) virus outbreak in the summer and fall of 1999 in new york state resulted in bird deaths in new york, new jersey, and connecticut. from august to december 1999, 295 dead birds were laboratory-confirmed with wn virus infection; 262 (89%) were american crows (corvus brachyrhynchos). the new york state department of health received reports of 17,339 dead birds, including 5,697 (33%) crows; in connecticut 1,040 dead crows were ... | 2001 | 11585521 |
| serologic evidence for west nile virus infection in birds in the new york city vicinity during an outbreak in 1999. | as part of an investigation of an encephalitis outbreak in new york city, we sampled 430 birds, representing 18 species in four orders, during september 13-23, 1999, in queens and surrounding counties. overall, 33% were positive for west nile (wn) virus-neutralizing antibodies, and 0.5% were positive for st. louis encephalitis virus-neutralizing antibodies. by county, queens had the most seropositive birds for wn virus (50%); species with the greatest seropositivity for wn virus (sample sizes we ... | 2001 | 11585522 |
| west nile virus isolates from mosquitoes in new york and new jersey, 1999. | an outbreak of encephalitis due to west nile (wn) virus occurred in new york city and the surrounding areas during 1999. mosquitoes were collected as part of a comprehensive surveillance program implemented to monitor the outbreak. more than 32,000 mosquitoes representing 24 species were tested, and 15 wn virus isolates were obtained. molecular techniques were used to identify the species represented in the wn virus-positive mosquito pools. most isolates were from pools containing culex pipiens ... | 2001 | 11585523 |
| dead bird surveillance as an early warning system for west nile virus. | as part of west nile (wn) virus surveillance in new york state in 2000, 71,332 ill or dead birds were reported; 17,571 (24.6%) of these were american crows. of 3,976 dead birds tested, 1,263 (31.8%) were positive for wn virus. viral activity was first confirmed in 60 of the state's 62 counties with wn virus-positive dead birds. pathologic findings compatible with wn virus were seen in 1,576 birds (39.6% of those tested), of which 832 (52.8%) were positive for wn virus. dead crow reports preceded ... | 2001 | 11585524 |
| west nile virus surveillance in connecticut in 2000: an intense epizootic without high risk for severe human disease. | in 1999, connecticut was one of three states in which west nile (wn) virus actively circulated prior to its recognition. in 2000, prospective surveillance was established, including monitoring bird deaths, testing dead crows, trapping and testing mosquitoes, testing horses and hospitalized humans with neurologic illness, and conducting a human seroprevalence survey. wn virus was first detected in a dead crow found on july 5 in fairfield county. ultimately, 1,095 dead crows, 14 mosquito pools, 7 ... | 2001 | 11585525 |
| mosquito surveillance and polymerase chain reaction detection of west nile virus, new york state. | west nile (wn) virus was detected in the metropolitan new york city (nyc) area during the summer and fall of 1999. sixty-two human cases, 7 fatal, were documented. the new york state department of health initiated a departmental effort to implement a statewide mosquito and virus surveillance system. during the 2000 arbovirus surveillance season, we collected 317,676 mosquitoes, submitted 9,952 pools for virus testing, and detected 363 wn virus-positive pools by polymerase chain reaction (pcr). e ... | 2001 | 11585526 |
| partial genetic characterization of west nile virus strains, new york state, 2000. | we analyzed nucleotide sequences from the envelope gene of 11 west nile (wn) virus strains collected in new york state during the 2000 transmission season to determine whether they differed genetically from each other and from the initial strain isolated in 1999. the complete envelope genes of these strains were amplified by reverse transcription-polymerase chain reaction. the resulting sequences were aligned, the genetic distances were computed, and a phylogenetic tree was constructed. ten (0.7 ... | 2001 | 11585527 |
| west nile encephalitis in israel, 1999: the new york connection. | we describe two cases of west nile (wn) encephalitis in a married couple in tel aviv, israel, in 1999. reverse transcription-polymerase chain reaction performed on a brain specimen from the husband detected a wn viral strain nearly identical to avian strains recovered in israel in 1998 (99.9% genomic sequence homology) and in new york in 1999 (99.8%). this result supports the hypothesis that the 1999 wn virus epidemic in the united states originated from the introduction of a strain that had bee ... | 2001 | 11585528 |
| dead crow densities and human cases of west nile virus, new york state, 2000. | in 2000, staten island, new york, reported 10 human west nile virus cases and high densities of dead crows. surrounding counties with <2 human cases had moderate dead crow densities, and upstate counties with no human cases had low dead crow densities. monitoring such densities may be helpful because this factor may be determined without the delays associated with specimen collection and testing. | 2001 | 11585529 |
| mosquito surveillance for west nile virus in connecticut, 2000: isolation from culex pipiens, cx. restuans, cx. salinarius, and culiseta melanura. | fourteen isolations of west nile (wn) virus were obtained from four mosquito species (culex pipiens [5], cx. restuans [4], cx. salinarius [2], and culiseta melanura [3]) in statewide surveillance conducted from june through october 2000. most isolates were obtained from mosquitoes collected in densely populated residential locales in fairfield and new haven counties, where the highest rates of dead crow sightings were reported and where wn virus was detected in 1999. minimum field infection rate ... | 2001 | 11585530 |
| west nile virus infection in birds and mosquitoes, new york state, 2000. | west nile (wn) virus was found throughout new york state in 2000, with the epicenter in new york city and surrounding counties. we tested 3,403 dead birds and 9,954 mosquito pools for wn virus during the transmission season. sixty-three avian species, representing 30 families and 14 orders, tested positive for wn virus. the highest proportion of dead birds that tested positive for wn virus was in american crows in the epicenter (67% positive, n=907). eight mosquito species, representing four gen ... | 2001 | 11585532 |
| west nile fever outbreak, israel, 2000: epidemiologic aspects. | from august 1 to october 31, 2000, 417 cases of west nile (wn) fever were serologically confirmed throughout israel; 326 (78%) were hospitalized patients. cases were distributed throughout the country; the highest incidence was in central israel, the most populated part. men and women were equally affected, and their mean age was 54+/-23.8 years (range 6 months to 95 years). incidence per 1,000 population increased from 0.01 in the 1st decade of life to 0.87 in the 9th decade. there were 35 deat ... | 2001 | 11585533 |
| west nile outbreak in horses in southern france, 2000: the return after 35 years. | on september 6, 2000, two cases of equine encephalitis caused by west nile (wn) virus were reported in southern france (hérault province), near camargue national park, where a wn outbreak occurred in 1962. through november 30, 76 cases were laboratory confirmed among 131 equines with neurologic disorders. the last confirmed case was on november 3, 2000. all but three cases were located in a region nicknamed "la petite camargue," which has several large marshes, numerous colonies of migratory and ... | 2001 | 11585534 |
| the relationships between west nile and kunjin viruses. | until recently, west nile (wn) and kunjin (kun) viruses were classified as distinct types in the flavivirus genus. however, genetic and antigenic studies on isolates of these two viruses indicate that the relationship between them is more complex. to better define this relationship, we performed sequence analyses on 32 isolates of kun virus and 28 isolates of wn virus from different geographic areas, including a wn isolate from the recent outbreak in new york. sequence comparisons showed that th ... | 2001 | 11585535 |
| rapid determination of hla b*07 ligands from the west nile virus ny99 genome. | defined t cell epitopes for west nile (wn) virus may be useful for developing subunit vaccines against wn virus infection and diagnostic reagents to detect wn virus-specific immune response. we applied a bioinformatics (epimatrix) approach to search the wn virus ny99 genome for hla b*07 restricted cytotoxic t cell (ctl) epitopes. ninety-five of 3,433 wn virus peptides scored above a predetermined cutoff, suggesting that these would be likely to bind to hla b*07 and would also be likely candidate ... | 2001 | 11585536 |
| west nile virus infection in the golden hamster (mesocricetus auratus): a model for west nile encephalitis. | this report describes a new hamster model for west nile (wn) virus encephalitis. following intraperitoneal inoculation of a new york isolate of wn virus, hamsters had moderate viremia of 5 to 6 days in duration, followed by the development of humoral antibodies. encephalitic symptoms began 6 days after infection; about half the animals died between the seventh and 14th days. the appearance of viral antigen in the brain and neuronal degeneration also began on the sixth day. wn virus was cultured ... | 2001 | 11585537 |
| experimental infection of chickens as candidate sentinels for west nile virus. | we evaluated the susceptibility, duration and intensity of viremia, and serologic responses of chickens to west nile (wn) virus (wnv-ny99) infection by needle, mosquito, or oral inoculation. none of 21 infected chickens developed clinical disease, and all these developed neutralizing antibodies. although viremias were detectable in all but one chicken, the magnitude (mean peak viremia <10,000 pfu/ml) was deemed insufficient to infect vector mosquitoes. wnv-ny99 was detected in cloacal and/or thr ... | 2001 | 11585538 |
| widespread west nile virus activity, eastern united states, 2000. | in 1999, the u.s. west nile (wn) virus epidemic was preceded by widespread reports of avian deaths. in 2000, arbonet, a cooperative wn virus surveillance system, was implemented to monitor the sentinel epizootic that precedes human infection. this report summarizes 2000 surveillance data, documents widespread virus activity in 2000, and demonstrates the utility of monitoring virus activity in animals to identify human risk for infection. | 2001 | 11585539 |
| exposure of domestic mammals to west nile virus during an outbreak of human encephalitis, new york city, 1999. | we evaluated west nile (wn) virus seroprevalence in healthy horses, dogs, and cats in new york city after an outbreak of human wn virus encephalitis in 1999. two (3%) of 73 horses, 10 (5%) of 189 dogs, and none of 12 cats tested positive for wn virus-neutralizing antibodies. domestic mammals should be evaluated as sentinels for local wn virus activity and predictors of the infection in humans. | 2001 | 11585540 |
| detection of north american west nile virus in animal tissue by a reverse transcription-nested polymerase chain reaction assay. | a traditional single-stage reverse transcription-polymerase chain reaction (rt-pcr) procedure is effective in determining west nile (wn) virus in avian tissue and infected cell cultures. however, the procedure lacks the sensitivity to detect wn virus in equine tissue. we describe an rt-nested pcr (rt-npcr) procedure that identifies the north american strain of wn virus directly in equine and avian tissues. | 2001 | 11585541 |
| west nile virus in overwintering culex mosquitoes, new york city, 2000. | after the 1999 west nile (wn) encephalitis outbreak in new york, 2,300 overwintering adult mosquitoes were tested for wn virus by cell culture and reverse transcriptase-polymerase chain reaction. wn viral rna and live virus were found in pools of culex mosquitoes. persistence in overwintering cx. pipiens may be important in the maintenance of wn virus in the northeastern united states. | 2001 | 11585542 |
| west nile virus outbreak among horses in new york state, 1999 and 2000. | west nile (wn) virus was identified in the western hemisphere in 1999. along with human encephalitis cases, 20 equine cases of wn virus were detected in 1999 and 23 equine cases in 2000 in new york. during both years, the equine cases occurred after human cases in new york had been identified. | 2001 | 11585543 |
| isolation and characterization of west nile virus from the blood of viremic patients during the 2000 outbreak in israel. | we report the isolation of west nile (wn) virus from four patient serum samples submitted for diagnosis during an outbreak of wn fever in israel in 2000. sequencing and phylogenetic analysis revealed two lineages, one closely related to a 1999 new york isolate and the other to a 1999 russian isolate. | 2001 | 11585544 |
| fatal encephalitis and myocarditis in young domestic geese (anser anser domesticus) caused by west nile virus. | during 1999 and 2000, a disease outbreak of west nile (wn) virus occurred in humans, horses, and wild and zoological birds in the northeastern usa. in our experiments, wn virus infection of young domestic geese (anser anser domesticus) caused depression, weight loss, torticollis, opisthotonus, and death with accompanying encephalitis and myocarditis. based on this experimental study and a field outbreak in israel, wn virus is a disease threat to young goslings and viremia levels are potentially ... | 2001 | 11585545 |
| treatment of west nile virus encephalitis with intravenous immunoglobulin. | | 2001 | 11585547 |
| ross river virus transmission, infection, and disease: a cross-disciplinary review. | ross river virus (rrv) is a fascinating, important arbovirus that is endemic and enzootic in australia and papua new guinea and was epidemic in the south pacific in 1979 and 1980. infection with rrv may cause disease in humans, typically presenting as peripheral polyarthralgia or arthritis, sometimes with fever and rash. rrv disease notifications in australia average 5,000 per year. the first well-described outbreak occurred in 1928. during world war ii there were more outbreaks, and the name ep ... | 2001 | 11585790 |
| clinical findings of west nile virus infection in hospitalized patients, new york and new jersey, 2000. | outbreaks of west nile (wn) virus occurred in the new york metropolitan area in 1999 and 2000. nineteen patients diagnosed with wn infection were hospitalized in new york and new jersey in 2000 and were included in this review. eleven patients had encephalitis or meningoencephalitis, and eight had meningitis alone. ages of patients ranged from 36 to 87 years (median 63 years). fever and neurologic and gastrointestinal symptoms predominated. severe muscle weakness on neurologic examination was fo ... | 2001 | 11589170 |
| equine west nile encephalitis, united states. | after the 1999 outbreak of west nile (wn) encephalitis in new york horses, a case definition was developed that specified the clinical signs, coupled with laboratory test results, required to classify cases of wn encephalitis in equines as either probable or confirmed. in 2000, 60 horses from seven states met the criteria for a confirmed case. the cumulative experience from clinical observations and diagnostic testing during the 1999 and 2000 outbreaks of wn encephalitis in horses will contribut ... | 2001 | 11589171 |
| west nile virus infection in mosquitoes, birds, horses, and humans, staten island, new york, 2000. | west nile (wn) virus transmission in the united states during 2000 was most intense on staten island, new york, where 10 neurologic illnesses among humans and 2 among horses occurred. wn virus was isolated from aedes vexans, culex pipiens, cx. salinarius, ochlerotatus triseriatus, and psorophora ferox, and wn viral rna was detected in anopheles punctipennis. an elevated weekly minimum infection rate (mir) for cx. pipiens and increased dead bird density were present for 2 weeks before the first h ... | 2001 | 11589172 |
| comparative west nile virus detection in organs of naturally infected american crows (corvus brachyrhynchos). | widespread deaths of american crows (corvus brachyrhynchos)were associated with the 1999 outbreak of west nile (wn) virus in the new york city region. we compared six organs from 20 crow carcasses as targets for wn virus detection. half the carcasses had at least one positive test result for wn virus infection. the brain was the most sensitive test organ; it was the only positive organ for three of the positive crows. the sensitivity of crow organs as targets for wn virus detection makes crow de ... | 2001 | 11592255 |
| west nile encephalitis: an emerging disease in the united states. | in 1999, an epidemic of west nile virus (wnv) encephalitis occurred in new york city (nyc) and 2 surrounding new york counties. simultaneously, an epizootic among american crows and other bird species occurred in 4 states. indigenous transmission of wnv had never been documented in the western hemisphere until this epidemic. in 2000, the epizootic expanded to 12 states and the district of columbia, and the epidemic continued in nyc, 5 new jersey counties, and 1 connecticut county. in addition to ... | 2001 | 11595987 |
| isolation and characterization of noncytopathic pestivirus mutants reveals a role for nonstructural protein ns4b in viral cytopathogenicity. | isolates of bovine viral diarrhea virus (bvdv), the prototype pestivirus, are divided into cytopathic (cp) and noncytopathic (ncp) biotypes according to their effect on cultured cells. the cp viruses also differ from ncp viruses by the production of viral nonstructural protein ns3. however, the mechanism by which cp viruses induce cytopathic effect in cell culture remains unknown. here we used a genetic approach to isolate ncp variants that arose from a cp virus at low frequency. a bicistronic b ... | 2001 | 11602707 |
| assembly and maturation of the flavivirus kunjin virus appear to occur in the rough endoplasmic reticulum and along the secretory pathway, respectively. | the intracellular assembly site for flaviviruses in currently not known but is presumed to be located within the lumen of the rough endoplasmic reticulum (rer). building on previous studies involving immunofluorescence (if) and cryoimmunoelectron microscopy of kunjin virus (kun)-infected cells, we sought to identify the steps involved in the assembly and maturation of kun. thus, using antibodies directed against envelope protein e in if analysis, we found the accumulation of e within regions coi ... | 2001 | 11602720 |
| neuroadapted yellow fever virus 17d: genetic and biological characterization of a highly mouse-neurovirulent virus and its infectious molecular clone. | a neuroadapted strain of yellow fever virus (yfv) 17d derived from a multiply mouse brain-passaged virus (porterfield yf17d) was additionally passaged in scid and normal mice. the virulence properties of this virus (spyf) could be distinguished from nonneuroadapted virus (yf5.2iv, 17d infectious clone) by decreased average survival time in scid mice after peripheral inoculation, decreased average survival time in normal adult mice after intracerebral inoculation, and occurrence of neuroinvasiven ... | 2001 | 11602731 |
| weekly update: west nile virus activity--united states, september 19-25, 2001. | | 2001 | 11603368 |
| a phylogenetic approach to following west nile virus in connecticut. | the 1999 outbreak of west nile (wn) virus in the northeastern united states was the first known natural occurrence of this flavivirus in the western hemisphere. in 1999 and 2000, 82 independent connecticut wn virus isolates were cultured from nine species of birds, five species of mosquitoes, and one striped skunk. nucleotide sequences obtained from these isolates identified 30 genetic changes, compared with wn-ny99, in a 921-nt region of the viral genome beginning at nucleotide position 205 and ... | 2001 | 11606791 |
| prevalence of antibody against west nile virus in volunteer blood donors living in southeastern france. | | 2001 | 11606836 |
| perspectives. bioterror spotlights long neglect of public health system. | | 2001 | 11668878 |
| immunization of mice against west nile virus with recombinant envelope protein. | west nile (wn) virus is a mosquito-borne flavivirus that emerged in the united states in 1999 and can cause fatal encephalitis. envelope (e) protein cdna from a wn virus isolate recovered from culex pipiens in connecticut was expressed in escherichia coli. the recombinant e protein was purified and used as ag in immunoblot assays and immunization experiments. patients with wn virus infection had abs that recognized the recombinant e protein. c3h/hen mice immunized with e protein developed e prot ... | 2001 | 11673542 |
| a novel mechanism to explain protein abnormalities in schizophrenia based on the flavivirus resistance gene. | the geographical distribution of schizophrenia was previously shown to correlate with the global distribution of tick-borne flaviviruses. the correlation suggests a natural resistance gene to flaviviruses could be involved in schizophrenia. the flavivirus resistance gene, flv, a gene found in wild mice and certain in-bred strains, confers resistance to flaviviruses through the interaction of cellular proteins with the flaviviral 3' untranslated regions (utrs). although the sequence and product o ... | 2001 | 11673799 |
| west nile virus: a case study in how ny state health information infrastructure facilitates preparation and response to disease outbreaks. | new york's (ny) health information network (hin) provided timely access to west nile virus (wnv) data during the initial outbreak in the late summer 1999. in december 1999, ny developed a plan to deal with wnv in 2000 that required an integrated surveillance system for humans, birds, mammals, and mosquitoes. the hin infrastructure allowed ny to deploy this system statewide in three months. local health departments throughout ny used the system to report, track, and retrieve surveillance data as ... | 2001 | 11680034 |
| faqs about the west nile virus. | | 2001 | 11682792 |
| enantiomeric synthesis of d- and l-cyclopentenyl nucleosides and their antiviral activity against hiv and west nile virus. | enantiomeric synthesis of d- and l-cyclopentenyl nucleosides and their antiviral activity against hiv and west nile virus are described. the key intermediate (-)- and (+)-cyclopentenyl alcohols (7 and 15) were prepared from d-gamma-ribonolactone and d-ribose, respectively. coupling of 7 with appropriately blocked purine and pyrimidine bases via the mitsunobu reaction followed by deprotection afforded the target l-(+)-cyclopentenyl nucleosides (24-28, 31, 33, and 36). d-(-)-cyclopentenyl nucleosi ... | 2001 | 11689085 |
| experimental infections of pigs with japanese encephalitis virus and closely related australian flaviviruses. | the flavivirus japanese encephalitis (je) virus has recently emerged in the australasian region. to investigate the involvement of infections with related enzootic flaviviruses, namely murray valley encephalitis (mve) virus and kunjin (kun) virus, on immunity of pigs to je virus and to provide a basis for interpretation of serologic data, experimental infections were conducted with combinations of these viruses. antibody responses to primary and secondary infections were evaluated using panels o ... | 2001 | 11693888 |
| west nile virus infection may be greater than previously thought. | | 2001 | 11697102 |
| [patient with west nile fever in the netherlands]. | a 45-year-old patient was admitted with high fever and inadequate behaviour. she had recently stayed in israel. extensive investigation suggested a viral infection, but the cause was not established. her partner suggested the possibility of west nile virus infection, based upon information he had found on the internet. serology was performed and specific igm and igg antibodies were demonstrated, but a paired serum sample was not available. the patient recovered spontaneously. the west nile virus ... | 2001 | 11715596 |
| nation's zoos and aquariums help track west nile virus. | | 2001 | 11724163 |
| nucleic acid sequence-based amplification assays for rapid detection of west nile and st. louis encephalitis viruses. | the development and application of nucleic acid sequence-based amplification (nasba) assays for the detection of west nile (wn) and st. louis encephalitis (sle) viruses are reported. two unique detection formats were developed for the nasba assays: a postamplification detection step with a virus-specific internal capture probe and electrochemiluminescence (nasba-ecl assay) and a real-time assay with 6-carboxyfluorescein-labeled virus-specific molecular beacon probes (nasba-beacon assay). the sen ... | 2001 | 11724870 |
| west nile virus. | | 2001 | 11734745 |
| transport and budding at two distinct sites of visible nucleocapsids of west nile (sarafend) virus. | it has been difficult to detect and visualize the physical nucleocapsid particles during the replication process of the flaviviruses. the use of cryo-immunoelectron microscopy has clearly revealed the capsid proteins and nucleocapsid particles of west nile (sarafend) virus (a flavivirus) for the first time. physical nucleocapsid particles accumulated in large numbers from 8 hr postinfection. double immunolabeling of the envelope and capsid proteins showed a close association of these structural ... | 2001 | 11745942 |
| vector competence of selected north american culex and coquillettidia mosquitoes for west nile virus. | to control west nile virus (wnv), it is necessary to know which mosquitoes are able to transmit this virus. therefore, we evaluated the wnv vector potential of several north american mosquito species. culex restuans and cx. salinarius, two species from which wnv was isolated in new york in 2000, were efficient laboratory vectors. cx. quinquefasciatus and cx. nigripalpus from florida were competent but only moderately efficient vectors. coquillettidia perturbans was an inefficient laboratory vect ... | 2001 | 11747732 |
| using a dynamic hydrology model to predict mosquito abundances in flood and swamp water. | we modeled surface wetness at high resolution, using a dynamic hydrology model, to predict flood and swamp water mosquito abundances. historical meteorologic data, as well as topographic, soil, and vegetation data, were used to model surface wetness and identify potential fresh and swamp water breeding habitats in two northern new jersey watersheds. surface wetness was positively associated with the subsequent abundance of the dominant floodwater mosquito species, aedes vexans, and the swamp wat ... | 2002 | 11749741 |
| efficacy of interferon alpha-2b and ribavirin against west nile virus in vitro. | | 2002 | 11749765 |
| from the centers for disease control and prevention. west nile virus activity--united states, october 17-23, 2001. | | 2001 | 11757529 |
| discovery, distribution, and abundance of the newly introduced mosquito ochlerotatus japonicus (diptera: culicidae) in connecticut, usa. | the earliest documented specimen of an exotic east asian mosquito ochlerotatus (finlaya) japonicis japonicus (theobald) in the western hemisphere is reported along with the results of a state wide survey to determine the distribution and abundance of this mosquito in connecticut. ochlerotatus japonicus was collected from 87 locations in eight counties. it is established throughout the state and occurs in a variety of natural and artificial container habitats including discarded tire casings, bir ... | 2001 | 11761373 |
| molecular dissection of the semliki forest virus homotrimer reveals two functionally distinct regions of the fusion protein. | semliki forest virus (sfv) is an enveloped alphavirus that infects cells via a membrane fusion reaction triggered by the acidic ph of endosomes. in response to low ph, the e1 proteins on the virus membrane undergo a series of conformational changes, resulting in the formation of a stable e1 homotrimer. little is known about the structural basis of either the e1 conformational changes or the resulting homotrimer or about the mechanism of action of the homotrimer in fusion. here, the e1 homotrimer ... | 2002 | 11773395 |
| laboratory diagnosis of central nervous system infections. | the laboratory diagnosis of cns infection is essential for optimal therapy. acute infection requires rapid turn-around testing with high predictive values, that is, the ability of a test to accurately identify those patients who do or do not have disease caused by a specific etiology. the gram's stain, fungal stains of direct smears, antigen testing for c. neoformans, and culture of bacteria, fungi, mycobacteria, and some viruses are important tests for the diagnosis of acute infection. the labo ... | 2001 | 11780267 |
| west nile virus myelitis. | a case report. | 2001 | 11781865 |
| west nile virus activity--eastern united states, 2001. | in 2000, arbonet, an enhanced human and animal surveillance system designed to monitor the geographic spread of west nile virus (wnv) in the united states and to identify areas at increased risk for human infections with wnv, detected wnv activity in the district of columbia and 12 states. this system, first implemented in the district of columbia and 20 states along the atlantic and gulf coasts, was later expanded throughout the continental united states. this report summarizes arbonet data fro ... | 2001 | 11787570 |
| outbreak of powassan encephalitis--maine and vermont, 1999-2001. | powassan (pow) virus, a north american tickborne flavivirus related to the eastern hemisphere's tickborne encephalitis viruses, was first isolated from a patient with encephalitis in 1958. during 1958-1998, 27 human pow encephalitis cases were reported from canada and the northeastern united states. during september 1999-july 2001, four maine and vermont residents with encephalitis were found to be infected with pow virus. these persons were tested for other arbovirus infections found in the nor ... | 2001 | 11787585 |
| west nile virus activity in the united states, 2001. | west nile virus (wnv) first appeared in the naive environment of the western hemisphere in 1999 in new york. genetic analysis determined that the virus was introduced into the united states from the mediterranean basin. this review discusses the spread of the virus in 2001 from the initial focus in queens, new york, to widespread activity in the eastern and midwestern united states. it concentrates on viral ecology, epizootiology, pathology, prediction, and prevention. research questions to furt ... | 2001 | 11792062 |
| travels of a virus. | | 2001 | 11793593 |
| update: surveillance for west nile virus in overwintering mosquitoes--new york, 2000. | following the 1999 west nile encephalitis outbreak in new york, guidelines were developed to direct surveillance, prevention, and control efforts in the eastern united states. as recommended in the guidelines, the new york city and new york state departments of health developed comprehensive west nile virus (wnv) surveillance and control programs, which included collecting overwintering culex mosquitoes to determine whether wnv might persist throughout the winter and initiate a zoonotic transmis ... | 2000 | 11795498 |
| prospects for development of a vaccine against the west nile virus. | vaccination provides the ultimate measure for personal protection against west nile disease. the development of a west nile vaccine for humans is justified by the uncertainty surrounding the size and frequency of future epidemics. at least two companies (acambis inc. and baxter/immuno) have initiated research and development on human vaccines. west nile encephalitis has also emerged as a significant problem for the equine industry. one major veterinary vaccine manufacturer (ft. dodge) is develop ... | 2001 | 11797767 |
| west nile encephalitis in russia 1999-2001: were we ready? are we ready? | in 1963-1993, several strains of west nile virus (wnv) were isolated from ticks, birds, and mosquitoes in the southern area of european russia and western siberia. in the same regions, anti-wnv antibody was found in 0.4-8% of healthy adult donors. sporadic human clinical cases were observed in the delta of the volga river. in spite of this, wnv infection was not considered by the health authorities as a potentially emerging infection, and the large wnv outbreak in southern russia, started in lat ... | 2001 | 11797768 |
| west nile in the mediterranean basin: 1950-2000. | recent west nile virus (wnv) outbreaks have occurred in the mediterranean basin. in algeria in 1994, about 50 human cases of wn encephalitis were suspected, including 8 fatal cases. in morocco in 1996, 94 equines were affected of which 42 died. in tunisia in 1997, 173 patients were hospitalized for encephalitis or meningoencephalitis. west nile serology performed on 129 patients was positive in 111 cases (87%) including 5 fatal cases. in italy in 1998, 14 horses located in tuscany were laborator ... | 2001 | 11797769 |
| west nile fever in israel 1999-2000: from geese to humans. | west nile virus (wnv) caused disease outbreaks in israel in the 1950s and the late 1970s. in 1998 an outbreak of wnv in goose farms and evidence of infection in dead migratory birds were reported. consequently, human diagnostic services for wnv were resumed, including virus isolation, serology, and rt-pcr. risk factors for infection were assessed by a serological survey in 1999, which revealed a seroprevalence of (a) 86% in people who had close contact with sick geese, (b) 28% in people in areas ... | 2001 | 11797770 |
| human arbovirus infections worldwide. | viral diseases transmitted by blood-feeding arthropods (arboviral diseases) are among the most important of the emerging infectious disease public health problems facing the world at the beginning of the third millennium. there are over 534 viruses listed in the arbovirus catalogue, approximately 134 of which have been shown to cause disease in humans. these are transmitted principally by mosquitoes and ticks. in the last two decades of the twentieth century, a few new arboviral diseases have be ... | 2001 | 11797771 |