Publications

comparison of two aquatic alphaviruses, salmon pancreas disease virus and sleeping disease virus, by using genome sequence analysis, monoclonal reactivity, and cross-infection.	cell culture isolates of salmon pancreas disease virus (spdv) of farmed atlantic salmon and sleeping disease virus (sdv) of rainbow trout were compared. excluding the poly(a) tracts, the genomic nucleotide sequences of spdv and sdv rnas include 11,919 and 11,900 nucleotides, respectively. phylogenetic analysis places spdv and sdv between the new world viruses of venezuelan equine encephalitis virus and eastern equine encephalitis virus and the old world viruses of aura virus and sindbis virus. w ...	2002	12021349
passive antibody administration (immediate immunity) as a specific defense against biological weapons.	the potential threat of biological warfare with a specific agent is proportional to the susceptibility of the population to that agent. preventing disease after exposure to a biological agent is partially a function of the immunity of the exposed individual. the only available countermeasure that can provide immediate immunity against a biological agent is passive antibody. unlike vaccines, which require time to induce protective immunity and depend on the host's ability to mount an immune respo ...	2002	12141970
detection by enzyme-linked immunosorbent assay of antibodies to west nile virus in birds.	we adapted an indirect immunoglobulin g enzyme-linked immunosorbent assay to facilitate studies of west nile virus (wnv) and evaluated its application to taxonomically diverse avian species. anti-wnv antibodies were detected in 23 bird species, including many exotic species, demonstrating its value in studies of wnv epizootiology.	2002	12194778
molecular genetic evidence that the hydrophobic anchors of glycoproteins e2 and e1 interact during assembly of alphaviruses.	chimeric alphaviruses in which the 6k and glycoprotein e1 moieties of sindbis virus are replaced with those of ross river virus grow very poorly, but upon passage, adapted variants arise that grow >100 times better. we have sequenced the entire domain encoding the e2, 6k, and e1 proteins of a number of these adapted variants and found that most acquired two amino acid changes, which had cumulative effects. in three independent passage series, amino acid 380 of e2, which is in the transmembrane d ...	2002	12239293
in vitro-assembled alphavirus core-like particles maintain a structure similar to that of nucleocapsid cores in mature virus.	in vitro-assembled core-like particles produced from alphavirus capsid protein and nucleic acid were studied by cryoelectron microscopy. these particles were found to have a diameter of 420 a with 240 copies of the capsid protein arranged in a t=4 icosahedral surface lattice, similar to the nucleocapsid core in mature virions. however, when the particles were subjected to gentle purification procedures, they were damaged, preventing generation of reliable structural information. similarly, purif ...	2002	12368355
age-dependent resistance to lethal alphavirus encephalitis in mice: analysis of gene expression in the central nervous system and identification of a novel interferon-inducible protective gene, mouse isg12.	several different mammalian neurotropic viruses produce an age-dependent encephalitis characterized by more severe disease in younger hosts. to elucidate potential factors that contribute to age-dependent resistance to lethal viral encephalitis, we compared central nervous system (cns) gene expression in neonatal and weanling mice that were either mock infected or infected intracerebrally with a recombinant strain, dste12q, of the prototype alphavirus sindbis virus. in 1-day-old mice, infection ...	2002	12388728
novel mutations that control the sphingolipid and cholesterol dependence of the semliki forest virus fusion protein.	the enveloped alphavirus semliki forest virus (sfv) infects cells via a membrane fusion reaction mediated by the e1 membrane protein. efficient sfv-membrane fusion requires the presence of cholesterol and sphingolipid in the target membrane. here we report on two mutants, srf-4 and srf-5, selected for growth in cholesterol-depleted cells. like the previously isolated srf-3 mutant (e1 proline 226 to serine), the phenotypes of the srf-4 and srf-5 mutants were conferred by single-amino-acid changes ...	2002	12438597
recombinant chimeric western and eastern equine encephalitis viruses as potential vaccine candidates.	chimeric cdna clones, pmwe1000 and pmwe2000, differing by five nucleotides at their 5' termini, were constructed of the 5' two-thirds of the western equine encephalitis (wee) virus genome (encoding nonstructural proteins) and the 3' one-third of the eastern equine encephalitis (eee) virus genome (encoding structural proteins). the wee virus sequences were derived from full-length cdna clones, pwe1000 and pwe2000, which were isogenic except for five nucleotide differences at their 5' termini and ...	2002	12441074
eastern equine encephalomyelitis virus infection in a horse from california.	a yearling quarter horse, which was raised in southern california, received routine vaccinations for prevention of infection by eastern equine encephalomyelitis virus (eeev). one week later, severe neurologic signs developed, and the horse was humanely destroyed. a vaccine-related encephalomyelitis was later suspected. a final diagnosis of eeev infection was established on the basis of acute onset of the neurologic signs, histopathologic and serologic testing, and isolation and molecular charact ...	2002	11927026
simulated overwintering of encephalitis viruses in diapausing female culex tarsalis (diptera: culicidae).	female culex tarsalis coquillett in reproductive diapause were infected per os or by intrathoracic inoculation with western equine encephalomyelitis (wee) or st. louis encephalitis (sle) viruses during "fall," maintained over a simulated "winter," and then tested for virus infection and transmission in vitro and in vivo after "vernal" termination. exposure of f1 progeny of field-collected females to cool temperatures and short daylength produced females in reproductive diapause that were relucta ...	2002	11931262
vector competence of california mosquitoes for west nile virus.	to identify the mosquito species competent for west nile virus (wnv) transmission, we evaluated 10 california species that are known vectors of other arboviruses or major pests: culex tarsalis, cx. pipiens pipiens, cx. p. quinquefasciatus, cx. stigmatosoma, cx. erythrothorax, ochlerotatus dorsalis, oc. melanimon, oc. sierrensis, aedes vexans, and culiseta inornata. all 10 became infected and were able to transmit wnv at some level. ochlerotatus, culiseta, and aedes were low to moderately efficie ...	2002	12498652
detection of encephalitis viruses in mosquitoes (diptera: culicidae) and avian tissues.	abstract diagnostic assays for the detection of st. louis encephalitis (sle) and western equine encephalomyelitis (wee) viruses in mosquito pools and avian tissues were compared for sensitivity, accuracy and specificity. the in situ enzyme immunoassay (eia), plaque assay on vero cells, passage in aedes albopictus skuse c6/36 and c7/10 cells, antigen capture enzyme immunoassay (ac-eia), and single and multiplex reverse transcription-polymerase chain reactions (rt-pcr) were evaluated using pools o ...	2002	11931031
surveillance for unexplained deaths and critical illnesses due to possibly infectious causes, united states, 1995-1998.	population-based surveillance for unexplained death and critical illness possibly due to infectious causes (unex) was conducted in four u.s. emerging infections program sites (population 7.7 million) from may 1, 1995, to december 31, 1998, to define the incidence, epidemiologic features, and etiology of this syndrome. a case was defined as death or critical illness in a hospitalized, previously healthy person, 1 to 49 years of age, with infection hallmarks but no cause identified after routine t ...	2002	11897065
sensitivity of the vectest antigen assay for eastern equine encephalitis and western equine encephalitis viruses.	vectest assays for detecting eastern equine encephalitis virus (eee) and western equine encephalitis virus (wee) antigen in mosquito pools were evaluated to determine their sensitivity and specificity by using a range of eee, wee, st. louis encephalitis virus (sle), and west nile virus (wn) dilutions as well as individual and pooled mosquitoes containing eee or wee. the eee test produced reliable positive results with samples containing > or = 5.3 log10 plaque-forming units (pfu) of eee/ml, and ...	2003	14710752
birds, migration and emerging zoonoses: west nile virus, lyme disease, influenza a and enteropathogens.	wild birds are important to public health because they carry emerging zoonotic pathogens, either as a reservoir host or by dispersing infected arthropod vectors. in addition, bird migration provides a mechanism for the establishment of new endemic foci of disease at great distances from where an infection was acquired. birds are central to the epidemiology of west nile virus (wnv) because they are the main amplifying host of the virus in nature. the initial spread of wnv in the u.s. along the ea ...	2003	15931279
serologic responses to eastern and western equine encephalomyelitis vaccination in previously vaccinated horses.	a prospective study was performed to determine the serologic response of previously vaccinated horses to revaccination against eastern and western equine encephalomyelitis (eee and wee). horses responded variably to each antigen, and some horses had low or undetectable antibodies 6 months after vaccination. some horses did not develop increasing titers to eee or wee despite recent vaccination. geometric mean titers peaked 2 weeks after revaccination and were significantly increased from before r ...	2003	15136985
detection of north american eastern and western equine encephalitis viruses by nucleic acid amplification assays.	we have developed nucleic acid sequence-based amplification (nasba), standard reverse transcription pcr (rt-pcr), and taqman nucleic acid amplification assays for the rapid detection of north american eastern equine encephalitis (eee) and western equine encephalitis (wee) viral rnas from samples collected in the field and clinical samples. the sensitivities of these assays have been compared to that of virus isolation. while all three types of nucleic acid amplification assays provide rapid dete ...	2003	12517876
experimental infection of california birds with western equine encephalomyelitis and st. louis encephalitis viruses.	a total of 27 bird species from the san joaquin and coachella valleys of california were inoculated subcutaneously with sympatric strains of western equine encephalomyelitis (wee) and st. louis encephalitis (sle) viruses. overall, 133 of 164 birds inoculated with wee virus developed a viremia detected by plaque assay; significantly greater than 72 of 163 birds inoculated with sle virus. host competence was calculated as the average number of days that each avian species had a viremia > or = 2 lo ...	2003	14765678
advances in life sciences and bioterrorism. risks, perspectives and responsibilities.		2003	12789408
detection of antibodies to alphaviruses and discrimination between antibodies to eastern and western equine encephalitis viruses in rabbit sera using a recombinant antigen and virus-specific monoclonal antibodies.	three arthropod-borne alphaviruses, western equine encephalitis viruses (weev), eastern equine encephalitis viruses (eeev) and venezuelan equine encephalitis viruses are the aetiological agents of a sometimes severe encephalomyelitis in equines and humans in the new world. with regard to the different ecology and epidemiology of these viruses, a method applied in serological screening should be able to distinguish between them as well as other related members of the genus alphavirus in the ameri ...	2003	14628996
limited potential for mosquito transmission of genetically engineered, live-attenuated western equine encephalitis virus vaccine candidates.	specific mutations associated with attenuation of venezuelan equine encephalitis (vee) virus in rodent models were identified during efforts to develop an improved vee vaccine. analogous mutations were produced in full-length cdna clones of the cba 87 strain of western equine encephalitis (wee) virus by site-directed mutagenesis in an attempt to develop an improved wee vaccine. isogenic viral strains with these mutations were recovered after transfection of baby hamster kidney cells with infecti ...	2003	12641414
a heterologous coiled coil can substitute for helix i of the sindbis virus capsid protein.	alphavirus core assembly proceeds along an assembly pathway involving a dimeric assembly intermediate. several regions of the alphavirus capsid protein have been implicated in promoting and stabilizing this dimerization, including a putative heptad repeat sequence named helix i. this sequence, which spans residues 38 to 55 of the sindbis virus capsid protein, was implicated in stabilizing dimeric contacts initiated through the c-terminal two-thirds of the capsid protein and nucleic acid. the stu ...	2003	12857904
recombinant sindbis/venezuelan equine encephalitis virus is highly attenuated and immunogenic.	venezuelan equine encephalitis virus (veev) is an important, naturally emerging zoonotic virus. veev was a significant human and equine pathogen for much of the past century, and recent outbreaks in venezuela and colombia (1995), with about 100,000 human cases, indicate that this virus still poses a serious public health threat. the live attenuated tc-83 vaccine strain of veev was developed in the 1960s using a traditional approach of serial passaging in tissue culture of the virulent trinidad d ...	2003	12915543
laboratory safety practices associated with potential agents of biocrime or bioterrorism.		2003	12843004
development of a biotin mimic tagged scfv antibody against western equine encephalitis virus: bacterial expression and refolding.	single chain antibodies (scfvs) are heavy and light chain variable domains connected by an artificial linker. because of their smaller size, scfvs show improved tissue penetration in vivo and reduced immunogenicity, making them ideal for therapeutic applications. we have cloned a scfv against western equine encephalitis (wee) using rdna technology. the scfv was generated from a hybridoma cell line (11d2) specific to the wee virus e1 glycoprotein and is arranged in the v(l)-v(h) orientation with ...	2004	15041214
effect of dose on house finch infection with western equine encephalomyelitis and st. louis encephalitis viruses.	house finches, carpodacus mexicanus, were experimentally infected with high and standard doses of western equine encephalomyelitis virus (weev) or st. louis encephalitis virus (slev) to determine whether high doses would produce an elevated viremia response and a high frequency of chronic infections. finches inoculated with approximately100,000 plaque forming units (pfu) of weev or slev produced viremia and antibody responses similar to those in finches inoculated with approximately 100 pfu of w ...	2004	15535631
western equine encephalomyelitis virus infection affects the life table characteristics of culex tarsalis (diptera: culicidae).	the life table attributes of culex tarsalis coquillett females infected experimentally by feeding on 4 and 6 log10 plaque-forming units (pfu) of western equine encephalomyelitis virus (weev) per milliliter of heparinized chicken blood were compared with an uninfected control group. females continually were offered 10% sucrose and an oviposition substrate and daily a blood meal through a biomembrane feeder. mortality (dead females) and fecundity (female eggs per female) were monitored daily until ...	2004	15535632
proteomics computational analyses suggest that the carboxyl terminal glycoproteins of bunyaviruses are class ii viral fusion protein (beta-penetrenes).	the bunyaviridae family of enveloped rna viruses includes five genuses, orthobunyaviruses, hantaviruses, phleboviruses, nairoviruses and tospoviruses. it has not been determined which bunyavirus protein mediates virion:cell membrane fusion. class ii viral fusion proteins (beta-penetrenes), encoded by members of the alphaviridae and flaviviridae, are comprised of three antiparallel beta sheet domains with an internal fusion peptide located at the end of domain ii. proteomics computational analyse ...	2004	15544707
encephalitis virus persistence in california birds: experimental infections in mourning doves (zenaidura macroura).	after-hatching and hatching year, mourning doves were infected by inoculation with either western equine encephalomyelitis (wee) or st. louis encephalitis (sle) viruses; some birds in each group also were treated with the immunosuppressant cyclophosphamide before and during infection. cyclophosphamide treatment significantly increased the wee viremia but did not alterthe antibody response. in contrast, cyclophosphamide-treated and -untreated doves did not develop a detectable sle viremia but bec ...	2004	15185951
causative agent of pogosta disease isolated from blood and skin lesions.	pogosta disease is a mosquito-borne viral disease in finland, which is clinically manifested by rash and arthritis; larger outbreaks occur in 7-year intervals. the causative agent of the disease has been suspected of being closely related to sindbis virus (sinv). we isolated sinv from five patients with acute pogosta disease during an outbreak in fall 2002 in finland. one virus strain was recovered from a whole blood sample and four other strains from skin lesions. the etiology of pogosta diseas ...	2004	15200824
evaluation of a western equine encephalitis recombinant e1 protein for protective immunity and diagnostics.	the e1 and e2 glycoproteins of western equine encephalitis (wee) are candidate antigens for wee subunit vaccine development. we have cloned the e1 gene of wee virus and expressed it in escherichia coli as inclusion bodies. the inclusion bodies were successfully solubilised, refolded and the immunogenicity of this unglycosylated protein was assessed in mice. immunization of mice with recombinant e1 protein generated both humoral and cell-mediated immune responses, indicating the recombinant e1 pr ...	2004	15498603
a 7-deaza-adenosine analog is a potent and selective inhibitor of hepatitis c virus replication with excellent pharmacokinetic properties.	improved treatments for chronic hepatitis c virus (hcv) infection are needed due to the suboptimal response rates and deleterious side effects associated with current treatment options. the triphosphates of 2'-c-methyl-adenosine and 2'-c-methyl-guanosine were previously shown to be potent inhibitors of the hcv rna-dependent rna polymerase (rdrp) that is responsible for the replication of viral rna in cells. here we demonstrate that the inclusion of a 7-deaza modification in a series of purine nu ...	2004	15388457
methods for studying the vector competence of culex tarsalis for western equine encephalomyelitis virus.	female culex tarsalis fed heparinized chicken blood-western equine encephalomyelitis virus (weev) mixtures through a biomembrane feeder were compared with females fed sweetened blood-virus mixtures presented in pledgets or as hanging drops or to restrained chickens with natural or artificial viremias. results indicated that sodium heparin did not adversely affect the infection of culex tarsalis with weev. overall advantages of the biomembrane system included 1) increased blood feeding frequency, ...	2004	15532927
acute encephalitis hospitalizations, california, 1990-1999: unrecognized arboviral encephalitis?	historically, western equine encephalomyelitis and st. louis encephalitis caused substantial human and equine illness and death in california. this study describes the epidemiology of encephalitis with data from 13,807 patients hospitalized in california with acute encephalitis from 1990 through 1999. the incidence of encephalitis hospitalizations decreased over this period. the greatest proportion of case-patients was hospitalized in the winter. encephalitis of unspecified origin was the most c ...	2004	15496246
duplex reverse transcription-pcr followed by nested pcr assays for detection and identification of brazilian alphaviruses and flaviviruses.	a new approach was developed for the rapid detection and identification of brazilian alphaviruses and flaviviruses. the methodology involves the genus-specific detection of alphavirus and flavivirus by a duplex reverse transcription-pcr (d-rt-pcr), followed by multiplex nested pcr (m-n-pcr) or nested pcr (n-pcr) assays for species-specific identification. by this protocol, 25 arboviruses were specifically detected and identified. detection levels between 10(1.3) and 10(3.5) 50% tissue culture in ...	2005	15695666
prophylaxis of acute respiratory virus infections using nucleic acid-based drugs.	acute respiratory virus infections such as sars and pandemic influenza are highly contagious diseases that cause global crisis, and inflict severe human mortality and morbidity. vaccines against these viruses are either unavailable or do not provide adequate protection. in the absence of effective vaccines, nucleic acid-based immunomodulators have the potential to offer effective, broad-spectrum protection against these deadly pathogens. poly iclc and cpg oligonucleotides are promising gene-base ...	2005	15755608
antibody response to culex tarsalis salivary gland antigens among sentinel chickens in california.	the arboviral surveillance program in california depends in part on sentinel chickens to detect western equine encephalomyelitis virus, st. louis encephalitis virus, and west nile virus activity. from 2000 through 2002, 1,578 serum specimens from 34 sentinel flocks in northern and southern california were tested for antibodies to culex tarsalis salivary gland antigens. sentinel chickens that were seropositive for mosquito salivary gland antigens were more likely to seroconvert to st. louis encep ...	2005	15827292
aerosol exposure to western equine encephalitis virus causes fever and encephalitis in cynomolgus macaques.	cynomolgus macaques were exposed by aerosol to a virulent strain of western equine encephalitis virus (weev). between 4 and 6 days after exposure, macaques had a significantly elevated temperature that lasted for 3-4 days. clinical signs of encephalitis began as the body temperature decreased, and then they rapidly increased in severity. cynomolgus macaques with clinical signs of encephalitis had elevated white cell counts in the blood caused mostly by increased numbers of segmented neutrophils ...	2005	16136459
coltiviruses and seadornaviruses in north america, europe, and asia.	coltiviruses are tickborne viruses of the genus coltivirus. the type species, colorado tick fever virus (from north america), has been isolated from patients with flulike syndromes, meningitis, encephalitis, and other severe complications. another coltivirus, eyach virus, has been isolated from ticks in france and germany and incriminated in febrile illnesses and neurologic syndromes. seadornaviruses are endemic in southeast asia, particularly indonesia and china. the prototype virus of the genu ...	2005	16318717
host range, amplification and arboviral disease emergence.	etiologic agents of arboviral diseases are primarily zoonotic pathogens that are maintained in nature in cycles involving arthropod transmission among a variety of susceptible reservoir hosts. in the simplest form of human exposure, spillover occurs from the enzootic cycle when humans enter zoonotic foci and/or enzootic amplification increases circulation near humans. examples include eastern (eeev) and western equine encephalitis viruses (weev), as well as west nile (wnv), st. louis encephaliti ...	2005	16358422
[detection of sindbis virus-specific nucleic acid with sybr green i real time pcr assay].	to develop a rapid, specific and sensitive method for detecting sindbis virus (sinv) with sybr green i real time pcr.	2005	16415993
health evaluation of free-ranging and captive blue-fronted amazon parrots (amazona aestiva) in the gran chaco, bolivia.	bolivia has a total of 47 species of psittacidae, seven of which have been identified in our study site, the semiarid gran chaco of the isoso. one species, the blue-fronted parrot (amazona aestiva), is frequently captured by local isoseño guaraní indians for exploitation on the national and international market. these birds are often temporarily housed in small villages under unhygienic conditions with poultry and other domestic species. on occasion, these parrots escape back to the wild. additi ...	2005	17312715
dna shuffling and screening strategies for improving vaccine efficacy.	the efficacy of vaccines can be improved by increasing their immunogenicity, broadening their crossprotective range, as well as by developing immunomodulators that can be coadministered with the vaccine antigen. one technology that can be applied to each of these aspects of vaccine development is molecularbreeding directed molecular evolution. essentially, this technology is used to evolve genes in vitro through an iterative process consisting of recombinant generation followed by selection of t ...	2005	15812242
nucleic acid amplification assays for detection of la crosse virus rna.	we report the development of nucleic acid sequence-based amplification (nasba) and quantitative real-time reverse transcription (rt)-pcr assays for the detection of la crosse (lac) virus in field-collected vector mosquito samples and human clinical samples. the sensitivities of these assays were compared to that of a standard plaque assay in vero cells. the nasba and quantitative real-time rt-pcr assays demonstrated sensitivities greater than that of the standard plaque assay. the specificities ...	2005	15815013
efficacy of dna vaccination against western equine encephalitis virus infection.	the efficacy of a dna vaccine against western equine encephalitis (wee) infection in mice was evaluated. the 26s structural region was expressed, in vitro from an internal t7 promoter using a rabbit reticulysate transcription/translation system; and from a cmv promoter after transfection into vero cell monolayers. the proteins synthesized were reactive with anti-wee virus (weev) antibodies, both in western blot analysis and histochemical staining, respectively. when the dna vaccine plasmid, pvhx ...	2005	15755611
effects of time after infection, mosquito genotype, and infectious viral dose on the dynamics of culex tarsalis vector competence for western equine encephalomyelitis virus.	the vector competence of culex tarsalis coquillett for the bfs 1703 strain of western equine encephalomyelitis virus (weev) changed significantly as a function of time after infection, mosquito genotype, and infectious virus dose. after ingesting a high virus dose (5 log10 plaque-forming units [pfu]/0.1 ml), female of the susceptible high virus producer (hvp) strain rapidly amplified the virus, developed a disseminated infection, and efficiently transmitted weev by 4 days postinfection (dpi). th ...	2006	17019773
infectivity variation and genetic diversity among strains of western equine encephalitis virus.	variation in infectivity and genetic diversity in the structural proteins were compared among eight strains of western equine encephalitis virus (weev) to investigate weev virulence at the molecular level. a lethal intranasal infectivity model of weev was developed in adult balb/c mice. all eight strains examined were 100 % lethal to adult mice in this model, but they varied considerably in the time to death. based on the time to death, the eight strains could be classified into two pathotypes: ...	2006	16847131
west nile virus epidemics in north america are driven by shifts in mosquito feeding behavior.	west nile virus (wnv) has caused repeated large-scale human epidemics in north america since it was first detected in 1999 and is now the dominant vector-borne disease in this continent. understanding the factors that determine the intensity of the spillover of this zoonotic pathogen from birds to humans (via mosquitoes) is a prerequisite for predicting and preventing human epidemics. we integrated mosquito feeding behavior with data on the population dynamics and wnv epidemiology of mosquitoes, ...	2006	16494532
serologic evidence of widespread everglades virus activity in dogs, florida.	everglades virus (evev), an alphavirus in the venezuelan equine encephalitis complex, circulates among rodents and vector mosquitoes in florida and occasionally infects humans. it causes febrile disease, sometimes accompanied by neurologic manifestations. although previous surveys showed high seroprevalence in humans, evev infections may be underdiagnosed because the disease is not severe enough to warrant a clinic visit or the undifferentiated presentations complicate diagnosis. documented evev ...	2006	17326938
vector competence of culiseta incidens and culex thriambus for west nile virus.	the vector competence of culiseta incidens (thomson) and culex thriambus dyar for west nile virus (wnv) were compared to cx. quinquefasciatus say or cx. tarsalis coquillett and cx. stigmatasoma dyar collected concurrently in california. culiseta incidens were less susceptible to oral infection than cx. quinquefasciatus, but transmitted virus at a significantly higher rate, thereby yielding comparable population transmission rates. culex thriambus was equally susceptible to oral infection and tra ...	2006	17304934
triaryl pyrazoline compound inhibits flavivirus rna replication.	triaryl pyrazoline {[5-(4-chloro-phenyl)-3-thiophen-2-yl-4,5-dihydro-pyrazol-1-yl]-phenyl-methanone} inhibits flavivirus infection in cell culture. the inhibitor was identified through high-throughput screening of a compound library using a luciferase-expressing west nile (wn) virus infection assay. the compound inhibited an epidemic strain of wn virus without detectable cytotoxicity (a 50% effective concentration of 28 microm and a compound concentration of >or=300 microm required to reduce 50% ...	2006	16569847
effects of temperature on the transmission of west nile virus by culex tarsalis (diptera: culicidae).	culex tarsalis coquillett females were infected with the ny99 strain of west nile virus (family flaviviridae, genus flavivirus, wnv) and then incubated under constant temperatures of 10-30 degrees c. at selected time intervals, transmission was attempted using an in vitro capillary tube assay. the median time from imbibing an infectious bloodmeal until infected females transmitted wnv (median extrinsic incubation period, eip50) was estimated by probit analysis. by regressing the eip rate (invers ...	2006	16619616
alphavirus capsid protein helix i controls a checkpoint in nucleocapsid core assembly.	the assembly of the alphavirus nucleocapsid core has been investigated using an in vitro assembly system. the c-terminal two-thirds of capsid protein (cp), residues 81 to 264 in sindbis virus (sinv), have been previously shown to have all the rna-cp and cp-cp contacts required for core assembly in vitro. helix i, which is located in the n-terminal dispensable region of the cp, has been proposed to stabilize the core by forming a coiled coil in the cp dimer formed by the interaction of residues 8 ...	2006	16940497
functions of the stem region of the semliki forest virus fusion protein during virus fusion and assembly.	membrane fusion of the alphaviruses is mediated by the e1 protein, a class ii virus membrane fusion protein. during fusion, e1 dissociates from its heterodimer interaction with the e2 protein and forms a target membrane-inserted e1 homotrimer. the structure of the homotrimer is that of a trimeric hairpin in which e1 domain iii and the stem region fold back toward the target membrane-inserted fusion peptide loop. the e1 stem region has a strictly conserved length and several highly conserved resi ...	2006	16971447
role of california (callipepla californica) and gambel's (callipepla gambelii) quail in the ecology of mosquito-borne encephalitis viruses in california, usa.	gambel's and california quail were infected repeatedly whenever western equine encephalomyelitis virus (weev), st. louis encephalitis virus (slev), and (wnv) west nile virus were active during summer in california. the timing of virus appearance and quail infection coincided well with the appearance of chicks in nature, leading us to hypothesize that large coveys containing these non-immune birds could be important in focal virus amplification in rural settings. however, experimental infection s ...	2006	16989564
the old world and new world alphaviruses use different virus-specific proteins for induction of transcriptional shutoff.	alphaviruses are widely distributed throughout the world. during the last few thousand years, the new world viruses, including venezuelan equine encephalitis virus (veev) and eastern equine encephalitis virus (eeev), evolved separately from those of the old world, i.e., sindbis virus (sinv) and semliki forest virus (sfv). nevertheless, the results of our study indicate that both groups have developed the same characteristic: their replication efficiently interferes with cellular transcription an ...	2007	17108023
capsid protein of eastern equine encephalitis virus inhibits host cell gene expression.	eastern equine encephalitis virus (eeev) causes sporadic but often severe cases of human and equine neurological disease in north america. to determine how eeev may evade innate immune responses, we screened individual eeev proteins for the ability to rescue the growth of a newcastle disease virus expressing green fluorescent protein (ndv-gfp) from the antiviral effects of interferon (ifn). only expression of the eeev capsid facilitated ndv-gfp replication. inhibition of the antiviral effects of ...	2007	17267491
comparison of immune responses of brown-headed cowbird and related blackbirds to west nile and other mosquito-borne encephalitis viruses.	the rapid geographic spread of west nile virus (family flaviviridae, genus flavivirus, wnv) across the united states has stimulated interest in comparative host infection studies to delineate competent avian hosts critical for viral amplification. we compared the host competence of four taxonomically related blackbird species (icteridae) after experimental infection with wnv and with two endemic, mosquito-borne encephalitis viruses, western equine encephalomyelitis virus (family togaviridae, gen ...	2007	17699082
differentiation of west nile and st. louis encephalitis virus infections by use of noninfectious virus-like particles with reduced cross-reactivity.	differential diagnosis of st. louis encephalitis virus (slev) and west nile virus (wnv) infections can be complicated due to the high degree of cross-reactivity observed in most serodiagnostic assays. in an effort to provide a more specific diagnostic test, we developed virus-like particle (vlp) antigens with reduced cross-reactivity for both slev and wnv by identifying and mutating envelope protein amino acids within the cross-reactive epitopes of vlp expression plasmids. to determine the serod ...	2007	17715375
immunological evaluation of escherichia coli expressed e2 protein of western equine encephalitis virus.	the western equine encephalitis virus (weev) is a potential biological warfare (bw) agent. the weev is endemic in western canada and has caused epidemics of "sleeping sickness" with a mortality rate of 7-9%. the e2 glycoprotein is a structural component of the weev and elicits production of neutralizing antibodies against the virus following an infection event. the envelope glycoprotein e2 is considered as the major target protein for the development of vaccines because it includes epitopes that ...	2007	17499379
single-dose, fast-acting vaccine candidate against western equine encephalitis virus completely protects mice from intranasal challenge with different strains of the virus.	western equine encephalitis virus (weev) causes a fatal infection of the central nervous system in humans and horses. however, neither human vaccine nor antiviral drug is available. we found previously that immunization of mice with two doses of an adenovirus-vectored weev vaccine, ad5-weev, confers complete protection against homologous weev challenge. in this paper, we report that a single-dose injection of ad5-weev completely protected mice against both homologous and heterologous strains of ...	2007	17630056
ecological correlates of buggy creek virus infection in oeciacus vicarius, southwestern nebraska, 2004.	buggy creek virus (family togaviridae, genus alphavirus, bcrv) is an alphavirus within the western equine encephalitis virus complex whose primary vector is the swallow bug, oeciacus vicarius horvath (hemiptera: cimicidae), an ectoparasite of the colonially nesting cliff swallow, petrochelidon pyrrhonota, that is also a frequent host for the virus. we investigated ecological correlates of bcrv infection in 100-bug pools at 14 different swallow colony sites in southwestern nebraska from summer 20 ...	2007	17294919
does feeding on infected mosquitoes (diptera: culicidae) enhance the role of song sparrows in the transmission of arboviruses in california?	song sparrows, melopiza melodia, inoculated subcutaneously with either western equine encephalomyelitis virus (family togaviridae, genus alphavirus, weev) or west nile virus (family flaviviridae, genus flavivirus, wnv) developed elevated viremias, and they were considered to be competent experimental hosts for both viruses. however, birds that ingested from three to 20 mosquitoes containing comparable amounts of either weev or wnv failed to become infected, indicating limited oral susceptibility ...	2007	17427703
complete protection of mice against a lethal dose challenge of western equine encephalitis virus after immunization with an adenovirus-vectored vaccine.	western equine encephalitis virus (weev) is an important pathogen for both humans and equines. the virus is also listed as a bioterrorism agent due to its ability for aerosol transmission with high mortality. no commercial vaccines or antiviral drugs are available for the prevention and treatment of weev infection in humans. in this paper, we constructed a recombinant weev vaccine, designated as ad5-weev, using a replication defective, human adenovirus serotype 5 (had5) as a delivery vector. ad5 ...	2007	17467858
pre- and post-exposure protection against western equine encephalitis virus after single inoculation with adenovirus vector expressing interferon alpha.	western equine encephalitis virus (weev) is a positive-sense, single-stranded rna virus which is transmitted to equines and humans through mosquito bites. weev infects the central nervous system with severe complications and even death. there are no human vaccine and antiviral drugs. we investigated whether adenovirus-mediated expression of interferon alpha could be used for pre- and post-exposure protection against a lethal weev challenge in mice. a human adenoviral vector (ad5-mifnalpha) expre ...	2007	17761207
effect of exogenous interferon and an interferon inducer on western equine encephalitis virus disease in a hamster model.	mice are used as models for western equine encephalitis virus (weev) infection, but high mortality is generally only seen with intracranial or intranasal challenge, while peripheral inoculation results in approximately 50% mortality and is not dose-dependent. hamsters were therefore studied as a model for weev infection. hamsters were highly sensitive to intraperitoneal (i.p.) infection with weev. disease progression was rapid, and virus titers in serum, brain, liver, and kidney of infected hams ...	2007	17118420
mass spectral data for 64 eluted peptides and structural modeling define peptide binding preferences for class i alleles in two chicken mhc-b haplotypes associated with opposite responses to marek's disease.	in the chicken, resistance to lymphomas that form following infection with oncogenic strains of marek's herpesvirus is strongly linked to the major histocompatibility complex (mhc)-b complex. mhc-b21 haplotype is associated with lower tumor-related mortality compared to other haplotypes including mhc-b13. the single, dominantly expressed class i gene (bf2) is postulated as responsible for the mhc-b haplotype association. we used mass spectrometry to identify peptides and structural modeling to d ...	2008	18612635
western equine encephalitis submergence: lack of evidence for a decline in virus virulence.	the incidence of western equine encephalitis (wee) in humans and equids peaked during the mid-20th century and has declined to fewer than 1-2 human cases annually during the past 20 years. using the mouse model, changes in wee virus (weev) virulence were investigated as a potential explanation for the decline in the number of cases. evaluation of 10 weev strains representing a variety of isolation locations, hosts, and all decades from the 1940's to the 1990's yielded no evidence of a decline in ...	2008	18801549
persistent west nile virus transmission and the apparent displacement st. louis encephalitis virus in southeastern california, 2003-2006.	west nile virus (family flaviviridae, genus flavivirus, wnv) invaded the colorado desert biome of southern california during summer 2003 and seemed to displace previously endemic st. louis encephalitis virus (family flaviviridae, genus flavivirus, slev, an antigenically similar flavivirus in the japanese encephalitis virus serocomplex). western equine encephalomyelitis virus (family togaviridae, genus alphavirus, weev), an antigenically distinct alphavirus, was detected during 2005 and 2006, ind ...	2008	18533445
development of human antibody fragments using antibody phage display for the detection and diagnosis of venezuelan equine encephalitis virus (veev).	venezuelan equine encephalitis virus (veev) belongs to the alphavirus group. several species of this family are also pathogenic to humans and are recognized as potential agents of biological warfare and terrorism. the objective of this work was the generation of recombinant antibodies for the detection of veev after a potential bioterrorism assault or an natural outbreak of veev.	2008	18764933
intensive early season adulticide applications decrease arbovirus transmission throughout the coachella valley, riverside county, california.	in the coachella valley of california the seasonal onset of st. louis encephalitis virus (slev), western equine encephalomyelitis virus (weev), and west nile virus (wnv) has been detected consistently at the shoreline of the salton sea near the community of north shore. the timing and intensity of initial amplification in the culex tarsalis coquillett/wild bird cycle at this focus seemed closely linked to the subsequent dispersal of virus to the rest of the coachella valley and perhaps southern ...	2008	18494603
temperature, viral genetics, and the transmission of west nile virus by culex pipiens mosquitoes.	the distribution and intensity of transmission of vector-borne pathogens can be strongly influenced by the competence of vectors. vector competence, in turn, can be influenced by temperature and viral genetics. west nile virus (wnv) was introduced into the united states of america in 1999 and subsequently spread throughout much of the americas. previously, we have shown that a novel genotype of wnv, wn02, first detected in 2001, spread across the us and was more efficient than the introduced gen ...	2008	18584026
the dynamic envelope of a fusion class ii virus. e3 domain of glycoprotein e2 precursor in semliki forest virus provides a unique contact with the fusion protein e1.	in alphaviruses, here represented by semliki forest virus, infection requires an acid-responsive spike configuration to facilitate membrane fusion. the creation of this relies on the chaperone function of glycoprotein e2 precursor (p62) and its maturation cleavage into the small external e3 and the membrane-anchored e2 glycoproteins. to reveal how the e3 domain of p62 exerts its control of spike functions, we determine the structure of a p62 cleavage-impaired mutant virus particle (sql) by elect ...	2008	18596032
the effects of midgut serine proteases on dengue virus type 2 infectivity of aedes aegypti.	dengue viruses (denv) cause significant morbidity and mortality worldwide and are transmitted by the mosquito aedes aegypti. mosquitoes become infected after ingesting a viremic bloodmeal, and molecular mechanisms involved in bloodmeal digestion may affect the ability of denv to infect the midgut. we used rna interference (rnai) to silence expression of four midgut serine proteases and assessed the effect of each rnai phenotype on denv-2 infectivity of aedes aegypti. silencing resulted in signif ...	2008	18689635
cloning, expression and purification of envelope proteins e1 and e2 of western equine encephalitis virus and potential use of them as antigens in immunoassays.	the genes encoding envelope proteins e1 and e2 of western equine encephalitis virus (weev) were respectively cloned into a prokaryotic t7 rna polymerase-regulated expression vector. the recombinant c-terminal 6xhis-tagged weev e1 and e2 were expressed in bacteria as inclusion bodies that were subsequently solubilized with 8m urea, purified by immobilized metal ion affinity chromatography and finally refolded using an arginine system. the purified 6xhis-tagged proteins showed 50kda bands as revea ...	2008	18054449
a tetravalent dengue vaccine based on a complex adenovirus vector provides significant protection in rhesus monkeys against all four serotypes of dengue virus.	nearly a third of the human population is at risk of infection with the four serotypes of dengue viruses, and it is estimated that more than 100 million infections occur each year. a licensed vaccine for dengue viruses has become a global health priority. a major challenge to developing a dengue vaccine is the necessity to produce fairly uniform protective immune responses to all four dengue virus serotypes. we have developed two bivalent dengue virus vaccines, using a complex adenovirus vector, ...	2008	18480438
discovery of frameshifting in alphavirus 6k resolves a 20-year enigma.	the genus alphavirus includes several potentially lethal human viruses. additionally, species such as sindbis virus and semliki forest virus are important vectors for gene therapy, vaccination and cancer research, and important models for virion assembly and structural analyses. the genome encodes nine known proteins, including the small '6k' protein. 6k appears to be involved in envelope protein processing, membrane permeabilization, virion assembly and virus budding. in protein gels, 6k migrat ...	2008	18822126
functional pseudotyping of human immunodeficiency virus type 1 vectors by western equine encephalitis virus envelope glycoprotein.	we investigated the ability of western equine encephalitis virus envelope glycoproteins (weev gp) to pseudotype lentiviral vectors. the titers of weev gp-pseudotyped human immunodeficiency virus type 1 (hiv) ranged as high as 8.0 x 10(4) iu/ml on permissive cells. sera from weev-infected mice specifically neutralized these pseudotypes; cell transduction was also sensitive to changes in ph. the host range of the pseudotyped particles in vitro was somewhat limited, which is atypical for most alpha ...	2008	18842711
effects of inducing or inhibiting apoptosis on sindbis virus replication in mosquito cells.	sindbis virus (sinv) is a mosquito-borne virus in the genus alphavirus, family togaviridae. like most alphaviruses, sinvs exhibit lytic infection (apoptosis) in many mammalian cell types, but are generally thought to cause persistent infection with only moderate cytopathic effects in mosquito cells. however, there have been several reports of apoptotic-like cell death in mosquitoes infected with alphaviruses or flaviviruses. given that apoptosis has been shown to be an antiviral response in othe ...	2008	18931060
arbovirus transmission by culex nigripalpus in florida, 2005.	understanding the transmission patterns of west nile and st. louis encephalitis viruses (family flaviviridae, genus flavivirus, wnv and slev) could result in an increased ability to predict transmission risk to humans. to examine transmission patterns between vector and host, we trapped mosquitoes in three florida counties from june to november 2005 by using chicken-baited lard can mosquito traps. these traps were used to monitor for presence of wnv and slev in mosquitoes and subsequent transmis ...	2008	18533444
limited interdecadal variation in mosquito (diptera: culicidae) and avian host competence for western equine encephalomyelitis virus (togaviridae: alphavirus).	historically, western equine encephalomyelitis virus (weev) caused large equine and human epidemics in the americas from canada into argentina. despite recent enhanced surveillance for west nile virus, there have been few reports of equine or human cases and little documented enzootic activity of weev. during the past three years, weev has been active again in california, but without human or equine cases. in the current study, we compared host and vector competence of representative weev isolat ...	2008	18385369
inhibition of alphavirus infection in cell culture and in mice with antisense morpholino oligomers.	the genus alphavirus contains members that threaten human health, both as natural pathogens and as potential biological weapons. peptide-conjugated phosphorodiamidate morpholino oligomers (ppmo) enter cells readily and can inhibit viral replication through sequence-specific steric blockade of viral rna. sindbis virus (sinv) has low pathogenicity in humans and is regularly utilized as a model alphavirus. ppmo targeting the 5'-terminal and aug translation start site regions of the sinv genome bloc ...	2008	18468653
maturation-dependent responses of human neuronal cells to western equine encephalitis virus infection and type i interferons.	innate cell-autonomous antiviral responses are essential first lines of defense against central nervous system infections but may also contribute to neuropathogenesis. we investigated the relationships between innate immunity and neuronal differentiation using an in vitro culture system with human cell lines to analyze cellular responses to the neurotropic alphavirus western equine encephalitis virus. human neuronal cells displayed a maturation-dependent reduction in virus-induced cytopathology ...	2008	18022665
bei resources: supporting antiviral research.	the biodefense and emerging infections research resources repository (bei resources) provides unique, quality-assured reagents to the scientific community for use in basic research and product development involving biodefense and emerging infectious diseases. these include microorganisms (up to biosafety level-3) on the national institute of allergy and infectious diseases (niaid) and centers for disease control and prevention (cdc) lists of category a, b and c priority pathogens. in addition to ...	2008	18675849
comparative thermostability of west nile, st. louis encephalitis, and western equine encephalomyelitis viruses during heat inactivation for serologic diagnostics.	during the monitoring of arbovirus seroprevalence in wild birds collected in california, we inadvertently made two isolates of western equine encephalomyelitis virus (weev) from california quail sera being tested by plaque reduction neutralization assay for antibodies against st louis encephalitis (slev) and west nile (wnv) viruses despite heating the sera at 56 degrees c for 30 minutes. these data prompted us to examine the thermostability of these viruses during heat treatment. the flaviviruse ...	2009	19407138
mode of transmission and the evolution of arbovirus virulence in mosquito vectors.	the traditional assumption that vector-borne pathogens should evolve towards a benign relationship with their arthropod vectors has been challenged on theoretical grounds and empirical evidence. however, in the case of arboviruses (arthropod-borne viruses), although a number of investigators have reported experimental evidence for virus-induced vector mortality, others have failed to detect any significant impact. whether this variation in the observed level of arbovirus virulence depends on bio ...	2009	19141420
repeated west nile virus epidemic transmission in kern county, california, 2004-2007.	west nile virus (wnv) has remained epidemic in kern county, ca, since its introduction in 2004 through 2007 when the human case annual incidence increased from 6-8 to 17 per 100,000, respectively. the 2007 increase in human infection was associated with contradicting surveillance indicators, including severe drought, warm spring but cool summer temperature anomalies, decreased rural and urban mosquito abundance but increased early season infection in urban culex quinquefasciatus say, moderate av ...	2009	19198528
identification of thieno[3,2-b]pyrrole derivatives as novel small molecule inhibitors of neurotropic alphaviruses.	neurotropic alphaviruses such as western, eastern, and venezuelan equine encephalitis viruses cause serious and potentially fatal central nervous system infections in humans and are high-priority potential bioterrorism agents. there are currently no widely available vaccines or licensed therapies for these virulent pathogens. to identify potential novel antiviral drugs, we developed a cell-based assay with a western equine encephalitis virus replicon that expresses a luciferase reporter gene and ...	2009	19239364
isolation of buggy creek virus (togaviridae: alphavirus) from field-collected eggs of oeciacus vicarius (hemiptera: cimicidae).	alphaviruses (togaviridae) rarely have been found to be vertically transmitted from female arthropods to their progeny. we report two isolations of buggy creek virus (bcrv), an ecologically unusual alphavirus related to western equine encephalomyelitis virus, from field-collected eggs of cimicid swallow bugs (oeciacus vicarius horvath), the principal vector for bcrv. ten percent of egg pools were positive for bcrv, and we estimated minimum infection rates to be 1.03 infected eggs per 1,000 teste ...	2009	19351091
virulence variation among isolates of western equine encephalitis virus in an outbred mouse model.	little is known about viral determinants of virulence associated with western equine encephalitis virus (weev). here, we have analysed six north american weev isolates in an outbred cd1 mouse model. full genome sequence analyses showed < or =2.7 % divergence among the six weev isolates. however, the percentage mortality and mean time to death (mtd) varied significantly when mice received subcutaneous injections of 10(3) p.f.u. of each virus. two weev strains, mcmillan (mcm) and imperial 181 (imp ...	2009	19403754
immune interference after sequential alphavirus vaccine vaccinations.	we compared the effect of order of administration of investigational alphavirus vaccines on neutralizing antibody response. volunteers who received the inactivated eastern and western equine encephalitis (eee and wee) vaccines before live attenuated venezuelan (vee) vaccine had significantly lower rates of antibody response than those receiving vee vaccine before eee and wee vaccines (66.7% vs. 80.6%; p=0.026). the odds of having a vee antibody non-response among those initially receiving eee an ...	2009	19576665
performance of the realstar chikungunya virus real-time reverse transcription-pcr kit.	a novel commercial chikungunya virus real-time reverse transcription-pcr (rt-pcr) kit was evaluated on a comprehensive panel of original patient samples. the assay was 100% sensitive and specific in comparison to a published real-time rt-pcr. viral loads from both assays were highly correlated. the kit proved to be suitable for routine use in patient care.	2009	19625474
environmental and biological factors influencing culex pipiens quinquefasciatus say (diptera: culicidae) vector competence for saint louis encephalitis virus.	complex interactions between environmental and biological factors influence the susceptibility of culex pipiens quinquefasciatus to st. louis encephalitis virus and could affect the epidemiology of virus transmission. similar interactions could have epidemiologic implications for other vector-virus systems. we conducted an experiment to examine four such factors in combination: mosquito age, extrinsic incubation temperature (eit), virus dose, and colony. the proportion of mosquitoes with body in ...	2009	19635881
similarities and differences in antagonism of neuron alpha/beta interferon responses by venezuelan equine encephalitis and sindbis alphaviruses.	venezuelan equine encephalitis virus (veev) is highly virulent in adult laboratory mice, while sindbis virus (sinv) is avirulent regardless of dose or inoculation route, dependent upon functioning alpha/beta interferon (ifn-alpha/beta) responses. we have examined each virus' resistance to and/or antagonism of ifn-alpha/beta responses in neurons, a cell type targeted by both viruses in mice, by infecting ifn-alpha/beta-treated or untreated primary cultures with viruses or virus-derived replicons ...	2009	19641001
chimeric alphavirus vaccine candidates protect mice from intranasal challenge with western equine encephalitis virus.	we developed two types of chimeric sindbis virus (sinv)/western equine encephalitis virus (weev) alphaviruses to investigate their potential use as live virus vaccines against wee. the first-generation vaccine candidate, sin/co92, was derived from structural protein genes of weev strain co92-1356, and two second-generation candidates were derived from weev strain mcmillan. for both first- and second-generation vaccine candidates, the nonstructural protein genes were derived from sinv strain ar33 ...	2009	19446595
vaccines for venezuelan equine encephalitis.	arboviruses are capable of causing encephalitis in animals and human population when transmitted by the vector or potentially via infectious aerosol. recent re-emergence of venezuelan equine encephalitis virus (veev) in south america emphasizes the importance of this pathogen to public health and veterinary medicine. despite its importance no antivirals or vaccines against veev are currently available in the usa. here we review some of the older and newer approaches aimed at generating a safe an ...	2009	19837294
emerging viral infections of the central nervous system: part 1.	in this 2-part review, i will focus on emerging virus infections of the central nervous system (cns). part 1 will introduce the basic features of emerging infections, including their definition, epidemiology, and the frequency of cns involvement. important mechanisms of emergence will be reviewed, including viruses spreading into new host ranges as exemplified by west nile virus (wnv), japanese encephalitis (je) virus, toscana virus, and enterovirus 71 (ev71). emerging infections also result fro ...	2009	19667214
exclusion of west nile virus superinfection through rna replication.	superinfection exclusion is the ability of an established viral infection to interfere with a second viral infection. using west nile virus (wnv) as a model, we show that replicating replicons in bhk-21 cells suppress subsequent wnv infection. the wnv replicon also suppresses superinfections of other flaviviruses but not nonflaviviruses. mode-of-action analysis indicates that the exclusion of wnv superinfection occurs at the step of rna synthesis. the continuous culturing of wnv in the replicon- ...	2009	19726510
replication cycle of chikungunya: a re-emerging arbovirus.	arboviruses (or arthropod-borne viruses), represent a threat for the new century. the 2005-2006 year unprecedented epidemics of chikungunya virus (chikv) in the french reunion island in the indian ocean, followed by several outbreaks in other parts of the world such as india, have attracted the attention of clinicians, scientists, and state authorities about the risks linked to this re-emerging mosquito-borne virus. chikv, which belongs to the alphaviruses genus, was not previously regarded as a ...	2009	19732931
aedes triseriatus females transovarially infected with la crosse virus mate more efficiently than uninfected mosquitoes.	the mating efficiencies (the percentage of females inseminated by males) of field-collected and laboratory-colonized aedes triseriatus (say) (diptera: culicidae) female mosquitoes transovarially infected or uninfected with la crosse virus (lacv) were compared. the females were placed in cages with age-matched males, and the insemination rates (number of inseminated females of the total number of females examined) were determined daily by detection of sperm in the spermathecae. lacv-infected mosq ...	2009	19769048