Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| elucidation of the topography and determination of the protective epitopes on the e glycoprotein of saint louis encephalitis virus by passive transfer with monoclonal antibodies. | we have identified and characterized eight antigenic epitopes on the 53,000 dalton envelope (e) glycoprotein of saint louis encephalitis (sle) virus by using monoclonal antibodies. one of these epitopes (e-1c) encoded for the type-specific biologic functions of hemagglutination (ha) and neutralization (n). injection of 50 ng of anti-e-1c antibody protected the majority of mice from peripheral challenge with 100 i.p. ld50 of sle virus. similar levels of protection with antibodies specific for oth ... | 1984 | 6198396 |
| the importance of disease induced changes in mammalian body temperature to mosquito blood feeding. | laboratory mice infected with rodent malaria (plasmodium berghei or p. chabaudi) or st. louis encephalitis virus (sle) were not hyperthermic during the infection period. however, all infected animals displayed pathogen-specific periods of hypothermia. hamsters infected with p. berghei were hyperthermic on day 7 postinfection (pi) but became hypothermic on day 8 pi and remained so until death, approximately 20 days pi. body temperatures of mice infected with p. yoelii were not significantly diffe ... | 1984 | 6142803 |
| [biological studies of st. louis encephalitis virus in majé, bayano]. | 1984 | 6149603 | |
| serologic evidence for widespread infection with la crosse and st. louis encephalitis viruses in the indiana human population. | the vast under-reporting of la crosse virus and st. louis encephalitis virus infections in indiana residents was evident when numerous inapparent infections were detected retrospectively using serum dilution neutralization analyses of serum obtained in november 1978-april 1979 from 10,208 persons (0.2% of the state's population). an antibody prevalence rate of 3.6% to st. louis encephalitis virus was detected in the sample population as a whole, with rates as high as 13.2% for residents of indiv ... | 1984 | 6328975 |
| immunoglobulin m antibody capture enzyme-linked immunosorbent assay for diagnosis of st. louis encephalitis. | sera from patients with st. louis encephalitis were tested with an immunoglobulin m (igm) antibody capture enzyme immunoassay (mac elisa). the assay used five reagents: antihuman igm, test serum, sucrose-acetone-extracted mouse brain antigen, broadly cross-reactive flavivirus monoclonal antibody conjugated to alkaline phosphatase, and substrate (p-nitrophenyl phosphate). mac elisa endpoint titers correlated (r = 0.893) with the absorbance value of a 1:100 dilution of patient serum. significant ( ... | 1984 | 6386882 |
| arthropod-borne virus infections of the central nervous system. | arthropod-borne viruses (arboviruses) are an important cause of meningoencephalitis in north america. this article considers the common features of the four major cns arbovirus infections in this country and gives detailed descriptions of the individual virus infections. | 1984 | 6503938 |
| [prevalence of antibodies against st. louis encephalitis virus in various marine birds from panama]. | 1984 | 6093203 | |
| purification of the structural and nonstructural proteins of st. louis encephalitis virus. | we have developed a procedure for purifying both the structural and nonstructural proteins of flaviviruses from lysates of infected cell cultures. the procedure involves: immunoprecipitation to concentrate viral proteins and eliminate most of the cellular proteins, preparative polyacrylamide gel electrophoresis to separate the viral proteins, and hydroxyapatite chromatography, which eliminates most of the unlabeled cellular protein. this procedure offers an improvement over previous purification ... | 1984 | 6099371 |
| the importance of autumn rainfall and sentinel flock location to understanding the epidemiology of st. louis encephalitis virus in indian river county, florida. | culex nigripalpus adults were collected from sentinel chickens at 4 sites in indian river co. (irc), florida. chickens located in well drained, open habitats attracted fewer cx. nigripalpus than did those located in a moist, forested area, but the number of mosquitoes collected in the open habitats increased significantly with heavy autumn rainfall. all st. louis encephalitis virus (sle) seroconversions (11/674) during a 7-year period were from chickens located in open, well drained habitats. a ... | 1985 | 2852706 |
| [meningoencephalitis caused by the st. louis encephalitis virus]. | 1985 | 3022104 | |
| distribution of dopa-oxidase isozymes among mosquito vectors of viral encephalitis. | distribution of dopa-oxidase isozymes in larval culex pipiens pipiens, culex pipiens quinquefasciatus and their hybrids was determined by agarose gel electrophoresis. three zones of enzyme activity were detected in the subspecific and hybrid populations. zone i was cathodic whereas zones ii and iii were anodic. electrophoretic variability was evident only in zone ii which was dimorphic for enzyme activity. zones i and iii were monomorphic. the subspecific and hybrid populations were distinguisha ... | 1985 | 3917888 |
| experimental studies of st. louis encephalitis virus in vertebrates. | serologically negative birds and mammals of species, known from other studies to be exposed naturally to st. louis encephalitis (sle) virus in memphis, tennessee, and other selected species were inoculated experimentally with strains of sle virus to determine their potential as natural hosts. mosquitoes (culex sp.) were allowed to feed on some of the inoculated vertebrate species, held for 14 days, and tested for sle infection. the cardinals (richmondena cardinalis), robins (turdus migratorius), ... | 1985 | 3999258 |
| arbovirus investigations in argentina, 1977-1980. i. historical aspects and description of study sites. | this is the introductory paper to a series on the ecology of arboviruses in argentina. epizootics of equine encephalitis have occurred since at least 1908, principally in the pampa and espinal biogeographic zones, with significant economic losses; human cases of encephalitis have been rare or absent. both western equine and eastern equine encephalitis viruses have been isolated from horses during these epizootics, but the mosquitoes responsible for transmission have not been identified. a number ... | 1985 | 4037184 |
| comparative susceptibility of five species of toxorhynchites mosquitoes to parenteral infection with dengue and other flaviviruses. | five species of colonized toxorhynchites mosquitoes were compared for relative susceptibility to parenteral infection with the four dengue serotypes and st. louis and japanese encephalitis viruses. tx. amboinensis, tx. brevipalpis, tx. rutilus, and tx. splendens were equally susceptible to infection with the dengue viruses, while tx. theobaldi was relatively resistant to infection with those viruses. all five mosquito species were equally susceptible to infection with the encephalitis viruses. t ... | 1985 | 2862802 |
| arbovirus investigations in argentina, 1977-1980. ii. arthropod collections and virus isolations from argentine mosquitoes. | prospective surveys for arboviruses were carried out in santa fe, corrientes, and chaco provinces, argentina, aperiodically during 1977-1980. a total of 313,233 mosquitoes and 598 biting flies other than mosquitoes were collected and tested for virus in 5,197 and 45 pools, respectively. forty virus strains were isolated, all from mosquitoes, as follows: santa fe province: 4 gamboa group viruses from aedeomyia squamipennis, 1 strain each of st. louis encephalitis virus from culex pipiens quinquef ... | 1985 | 2863989 |
| arbovirus investigations in argentina, 1977-1980. iii. identification and characterization of viruses isolated, including new subtypes of western and venezuelan equine encephalitis viruses and four new bunyaviruses (las maloyas, resistencia, barranqueras, and antequera). | forty viruses isolated from mosquitoes between 1977 and 1980 in argentina have been identified and characterized. nineteen strains of vee virus, identical by neutralization (n) tests, were shown by hemagglutination-inhibition tests with anti-e2 glycoprotein sera to represent a new subtype vi of the vee complex. rna oligonucleotide fingerprints of this virus were distinct from subtype i viruses. the virus was not lethal for english short-haired guinea pigs, indicating that it is probably not equi ... | 1985 | 2863990 |
| arbovirus investigations in argentina, 1977-1980. iv. serologic surveys and sentinel equine program. | serologic surveys of wild and domestic birds, wild mammals, and horses were conducted during arbovirus field studies in argentina from 1977 through 1980, a non-epizootic interval. the prevalence of neutralizing antibodies to eastern equine encephalitis (eee) was consistently higher than to western equine encephalitis (wee) virus in all species and all areas. the presence of antibodies in short-lived avian species and in young unvaccinated horses and the demonstration of seroconversions in horses ... | 1985 | 2863991 |
| isolation of st. louis encephalitis virus from adult dermacentor variabilis (acari: ixodidae). | 1985 | 2984423 | |
| premortem isolation of saint louis encephalitis virus: case report and implications for hospital and laboratory personnel. | 1985 | 2995935 | |
| amino-terminal amino acid sequences of structural proteins of three flaviviruses. | n-terminal amino acid sequences of structural proteins of three flaviviruses, yellow fever, st. louis encephalitis, and dengue-2 viruses, have been obtained. the glycoproteins of these three viruses are 52-60% conserved in the region sequenced, depending upon which pair of viruses are compared, and 40% of the amino acids are invariant in all three viruses. thus, flaviviruses are closely related and have in all probability descended from a common ancestor. furthermore, residues important in the s ... | 1985 | 2998002 |
| partial n-terminal amino acid sequences of three nonstructural proteins of two flaviviruses. | partial n-terminal amino acid sequences for the three largest nonstructural proteins of two flaviviruses, yellow fever virus and st. louis encephalitis virus, have been obtained. the determined sequences of these proteins exhibit significant amino acid sequence homology, and allow the positioning of these three nonstructural proteins in the polyprotein sequence deduced from the nucleotide sequence of yellow fever virus (c. m. rice, e. m. lenches, s. r. eddy, s. j. shin, r. l. sheets, and j. h. s ... | 1986 | 3008425 |
| arbovirus infections in several ontario mammals, 1975-1980. | serological studies for arboviruses were conducted on 725 animal sera collected in 22 ontario townships between 1975 and 1980 including 44 coyote (canis latrans), 277 red fox (vulpes vulpes), 192 raccoon (procyon lotor) and 212 striped skunk (mephitis mephitis). hemagglutination inhibition antibodies to two flaviviruses, namely st. louis encephalitis and powassan were found in 50% of coyote, 47% of skunk, 26% of fox and 10% of raccoon sera. similarly, hemagglutination inhibition antibodies to a ... | 1986 | 3017527 |
| relevance of detection of immunoglobulin m antibody response in birds used for arbovirus surveillance. | young chickens were inoculated with 5,000 pfu of eastern equine encephalitis (eee) virus and bled at intervals thereafter for determinations of hemagglutination-inhibiting (hi), neutralizing (n), immunoglobulin m (igm), and igg antibodies. hi, n, and igm antibodies were first detected 4 days after infection, and igg was detected 7 days after infection. all four antibodies persisted through day 90 after infection. hi, n, and igm antibody titers remained elevated and were not cross-reactive with t ... | 1986 | 3021813 |
| epitope mapping of flavivirus glycoproteins. | 1986 | 2428213 | |
| antigenic comparison of envelope protein e between japanese encephalitis virus and some other flaviviruses using monoclonal antibodies. | the antigenic relationships between japanese encephalitis (je) virus and several other flaviviruses have been investigated using anti-je virus monoclonal antibodies (mabs). seventeen mabs directed against envelope protein e of je virus were characterized and divided into eight mab groups based on reactivity patterns in haemagglutination inhibition test, neutralization (n) test, elisa and competitive binding assay with je virus. the results suggest the existence of at least eight epitopes on the ... | 1986 | 2432163 |
| entomological studies at an enzootic venezuelan equine encephalitis virus focus in guatemala, 1977-1980. | the ecology of several potential mosquito vectors of venezuelan equine encephalitis (vee) alphavirus was studied in an enzootic focus of that virus on the pacific coast of guatemala over a four-year period. four species-culex taeniopus, mansonia titillans, culex nigripalpus and aedes taeniorhynchus-were most prevalent during the wet season when transmission normally occurs. however, only cx. taeniopus yielded vee virus. the bloodfeeding patterns of these species revealed that ae. taeniorhynchus ... | 1986 | 2873752 |
| experimental vertical transmission of saint louis encephalitis virus by florida mosquitoes. | vertical transmission of st. louis encephalitis (sle) virus to f1 larval progeny was demonstrated in 8 species of mosquitoes which occur in florida: culex quinquefasciatus, cx. nigripalpus, cx. salinarius, cx. restuans, cx. opisthopus, anopheles quadrimaculatus, an. albimanus, and aedes taeniorhynchus. relatively high rates of such transmission were observed in ae. taeniorhynchus and vertical transmission to f1 adult progeny and venereal transmission from males to females also were demonstrated ... | 1986 | 2878627 |
| viremic enhancement due to transovarially acquired antibodies to st. louis encephalitis virus in birds. | adult house sparrows (passer domesticus) were captured and experimentally inoculated with st. louis encephalitis (sle) virus to produce high concentrations of circulating antiviral antibody. nestlings, 5-7 and 14-16 days of age, from sle immune adult females and challenged with sle virus, exhibited viremic enhancement by producing viremias of greater duration and magnitude than did controls. nestlings possessing maternal antibody and challenged with sle virus between 8 and 13 days of age did not ... | 1986 | 3735578 |
| partial nucleotide sequence of st. louis encephalitis virus rna: structural proteins, ns1, ns2a, and ns2b. | cdna clones of the st. louis encephalitis (sle) virus genome have been obtained and the nucleotide sequence of 4.7 kb corresponding to the 5' terminal half of the genome determined. the genome contains a 5' noncoding region of 98 nucleotides followed by a single continuous open reading frame that encodes three structural proteins in the order capsid (c), membrane precursor (prm)-membrane (m), and envelope (e). immediately following the c-terminus of e are located nonstructural proteins ns1 throu ... | 1987 | 3027980 |
| detection of st. louis encephalitis virus antigen in mosquitoes by capture enzyme immunoassay. | surveillance methods that measure st. louis encephalitis (sle) virus activity in nature may provide forewarning of its epidemic occurrence in humans. an antigen capture enzyme immunoassay was developed to detect sle virus in infected mosquitoes. the assay detected purified sle viral antigen at a concentration of 62 pg/0.1 ml when antigen was incubated overnight; 250 pg/0.1 ml was detected in a single-day assay (antigen incubated for 3 h). the assay detected 67.9 and 70.8% of laboratory-prepared ... | 1987 | 3029170 |
| st. louis encephalitis: lessons from the last decade. | in 1980 reeves wrote that epidemics of st. louis encephalitis (sle) are preventable by means of surveillance and vector abatement. this view is examined in the light of epidemic activity during the last decade (1977-1986), in which 9 discrete outbreaks occurred. in addition, 5 interactive factors (virus, vector, viremic host, human immunity, environmental temperature) described by reeves as essential to the development of an sle epidemic are reviewed in the light of recent research. although muc ... | 1987 | 3318523 |
| susceptibility of aedes albopictus c6/36 cells to viral infection. | the susceptibility of the c6/36 clone of aedes albopictus monolayer cell cultures was determined with 46 prototype viruses passed through three subcultures. viral growth was confirmed by titration of the passage material in other susceptible host systems. nineteen viruses demonstrated good growth in c6/36 cells: coxsackievirus group a type 10 and group b types 2, 3, 4, and 5; enterovirus 69; mumps virus; poliovirus types 1 to 3; reovirus types 1 to 3; vaccinia virus; dengue virus type 2; eastern ... | 1987 | 3611315 |
| isolation of cache valley virus and detection of antibody for selected arboviruses in michigan horses in 1980. | blood samples collected in september and november 1980 from 87 horses in southwestern michigan were examined for virus isolation and for plaque-reduction neutralizing antibody against selected arboviruses. cache valley virus was isolated from the blood of a clinically normal horse in st joseph county in september. the age-specific antibody prevalence for cache valley virus indicated enzootic transmission in the study area. the high antibody prevalence and the lack of age-specific antibody preval ... | 1987 | 3631684 |
| arbovirus isolations from mosquitoes collected during and after the 1982-1983 epizootic of western equine encephalitis in argentina. | mosquitoes were collected in santa fe and rio negro provinces, argentina, in 1982-1983 during a western equine encephalitis (wee) epizootic. totals of 153,084 mosquitoes from santa fe province and 484 from rio negro province were tested for virus in 2,351 pools. seventeen virus strains were isolated, all from santa fe collections, as follows: 4 wee, 6 venezuelan equine encephalitis, 1 st. louis encephalitis, 2 antequera, 1 maguari, 1 melao, 1 new vesiculovirus (calchaqui), and 1 gamboa. the wee ... | 1987 | 2880521 |
| epidemiologic aspects of a st. louis encephalitis outbreak in mesa county, colorado. | an epidemic of st. louis encephalitis in 1985 in mesa county, colorado, led to 17 cases, including one fatality. risk was associated with advanced age and residence in grand junction, the county's principal city. a trend was observed toward higher risk in females. however, increased risk in females was not associated with higher infection rates (increased exposure). capture enzyme immunoassays detected specific immunoglobulin m (igm) and immunoglobulin a after infection. a serosurvey of grand ju ... | 1987 | 2887107 |
| the discovery decade of arbovirus research in western north america, 1940-1949. | 1987 | 2891315 | |
| entomologic studies after a st. louis encephalitis epidemic in grand junction, colorado. | in 1986, after a st. louis encephalitis epidemic in grand junction, colorado, in 1985, vector mosquitoes in the city were surveyed to correlate their bionomics and infection rates with the occurrence of human disease. no human cases were reported, but mosquito surveillance disclosed st. louis encephalitis virus in culex tarsalis and culex pipiens pipiens. mosquitoes were collected with gravid traps designed to attract cx. p. pipiens and with centers for disease control light traps. culex p. pipi ... | 1988 | 2899394 |
| antigenic structure of the murray valley encephalitis virus e glycoprotein. | to complement our battery of st louis encephalitis (sle) virus monoclonal antibodies (mabs), we isolated and characterized mabs reactive with another member of the sle virus serocomplex, murray valley encephalitis (mve) virus. from 40 fusion products, we isolated 10 stable hybridomas. the combination of sle and mve virus mabs defined eight epitopes on the mve envelope (e) glycoprotein. six of these epitopes (e-1a, e-1c, e-1d, e-3, e-4a, e-4b) were identical to those previously demonstrated on sl ... | 1988 | 2453607 |
| nucleotide and complete amino acid sequences of kunjin virus: definitive gene order and characteristics of the virus-specified proteins. | a kunjin (kun) virus cdna sequence of 10664 nucleotides was obtained and it encoded a single open reading frame for 3433 amino acids. partial n-terminal amino acid analyses of kun virus-specified proteins identified the polyprotein cleavage sites and the definitive gene order. the gene order relative to that proposed for yellow fever (yf) virus is as follows: kun 5'-c.gp20.e.gp44.p19.p10.p71.(?).p21.p98-3' yf 5'-c.prm.e.ns1.ns2a.ns2b.ns3.ns4a.ns4b. ns5-3'. the order of putative signal sequences ... | 1988 | 2826659 |
| evidence that the mature form of the flavivirus nonstructural protein ns1 is a dimer. | evidence is presented which indicates that the dengue-2 virus nonstructural protein ns1 (soluble complement fixing antigen) exists in infected bhk and mosquito cell cultures as part of a stable oligomer. identification of the dissociation products of the isolated oligomer and comparison of the number of n-linked glycans in native and denatured ns1 is consistent with the idea that the high-molecular-weight form of ns1 is a homodimer. by analyzing lysates of bhk cells infected with st. louis encep ... | 1988 | 2827377 |
| sequence and secondary structure analysis of the 5'-terminal region of flavivirus genome rna. | the 5'-terminal noncoding region sequences were determined for the genome rnas of seven strains of st. louis encephalitis virus (slev) and one strain of west nile virus (wnv) using a single synthetic cdna primer complementary to the 5'-terminus of the coding region of a strain of wnv rna. the 5'-terminal sequences obtained for the slev and wnv rnas were compared with published sequences for yellow fever virus (yfv), murray valley encephalitis virus (mvev), and dengue virus. while only short regi ... | 1988 | 2829420 |
| a rapid dot immunoassay for the detection of serum antibodies to eastern equine encephalomyelitis and st. louis encephalitis viruses in sentinel chickens. | a dot enzyme-linked immunosorbent assay utilizing a novel membrane, polyvinylidene difluoride, is described. this assay was developed for the rapid detection of serum antibodies to eastern equine encephalomyelitis virus and st. louis encephalitis virus in sentinel chickens. antigens were spot-filtered through the membrane. membranes were dipped into small vials of sera. antigen-antibody complexes were detected with enzyme-conjugated antiglobulin which, when exposed to substrate, produced a color ... | 1988 | 2829636 |
| the st. louis encephalitis epidemic. | 1988 | 2839532 | |
| further observations on the mechanism of vertical transmission of flaviviruses by aedes mosquitoes. | as previously observed for dengue viruses, vertical (i.e., transgenerational) transmission of japanese and st. louis encephalitis viruses by aedes albopictus takes place when the fully formed egg, enclosed in the chorion, is oviposited. the demonstration of such a mechanism for three flaviviruses suggests that vertical transmission of all mosquito-borne flaviviruses may occur in the same manner. | 1988 | 2840833 |
| establishment and characterization of st louis encephalitis virus persistent infections in aedes and culex mosquito cell lines. | persistent infections with st louis encephalitis (sle) virus were established in three mosquito cell lines (aedes albopictus, a. dorsalis and culex tarsalis) and were maintained for over 2 years. all three persistently infected cell cultures shared two features: (i) no overt cytopathic effect and (ii) a relatively high proportion of cells infected (41 to 85%). the aedes persistently infected cultures were resistant to superinfection with the homologous virus but not heterologous viruses. two sig ... | 1988 | 2842432 |
| phenotypes of st louis encephalitis virus mutants produced in persistently infected mosquito cell cultures. | viral mutants that appeared during long-term persistent infections of mosquito cell cultures (aedes albopictus, a. dorsalis and culex tarsalis) with st louis encephalitis virus were characterized. evidence was obtained for the presence of temperature-sensitive mutants in the a. dorsalis and c. tarsalis persistently infected cultures, and small plaque mutants were predominant in all cultures except one of two cell cultures of c. tarsalis. virus from persistently infected a. albopictus cell cultur ... | 1988 | 2842433 |
| antibody prevalence of st. louis encephalitis virus in avian hosts in los angeles, california, 1986. | a study was conducted to determine the pattern of st. louis encephalitis (sle) virus activity in the avian populations of the los angeles metropolitan area in 1986. in total, 679 birds of 42 species were captured at 7 study sites. the overall prevalence of sle neutralizing (n) antibody of 3% indicated enzootic transmission. antibody prevalences were higher in birds sampled in the central part of the metropolitan area, which was consistent with other epidemiologic data. the use of specific avian ... | 1988 | 2852209 |
| stability of st. louis encephalitis viral antigen detected by enzyme immunoassay in infected mosquitoes. | the use of enzyme immunoassay to detect st. louis encephalitis (sle) viral antigen in vector mosquitoes enhances the effectiveness of surveillance because infected mosquitoes can be identified more rapidly than with conventional virus isolation systems and because it is a simple and accessible procedure. infectivity among mosquitoes experimentally infected with sle virus was lost within 24 h after the mosquitoes were stored at 27 degrees c and 80% relative humidity; however, viral antigen remain ... | 1988 | 2852675 |
| flavivirus vaccines. | diseases caused by flavivirus infection have been a scourge of mankind for over three centuries; with yellow fever, dengue fever and russian spring-summer encephalitis causing epidemics resulting in thousands of fatalities. due to the development of a safe and efficacious live-attenuated vaccine against yellow fever, this disease is no longer such a threat in countries where adequate vaccination is practised. a similarly safe and efficacious inactivated vaccine against central-european tick-born ... | 1988 | 2854336 |
| delaying virus maturation for a higher yield of cell associated virus antigens. | negligible amounts of virus were released when infected cells were maintained in low ionic strength medium. the cells accumulated a high titre of virus and its specific antigenic proteins, detected by complement-fixation test. the procedure has potential for production of virus subunit vaccines. | 1989 | 2481802 |
| kunjin virus isolates of australia are genetically homogeneous. | the genomes of 22 isolates of kunjin virus (kun) from australia were characterized and compared using rnase t1 oligonucleotide fingerprinting. the results show that all isolates belonged to one topotype, the distribution of which covered the entire australian continent. this finding is similar to that of murray valley encephalitis virus, but in contrast to the results reported for some other flaviviruses such as saint louis encephalitis virus. | 1989 | 2552010 |
| [serologic study of arbovirus in 2 localities of the juventud island]. | a serologic study is made in two population groups in the isle of youth. a total 268 blood samples in blotting paper are subjected to the hemagglutination inhibition technique, using the eastern equine encephalomyelitis, western equine encephalomyelitis, saint louis encephalitis, and dengue 2 viruses; 16% positivity to flavivirus was found. a second serum sample was taken in people positive by the hemagglutination inhibition technique in order to carry out the techniques of complement fixation a ... | 1989 | 2561798 |
| surveillance of st. louis encephalitis virus vectors in grand junction, colorado, in 1987. | grand junction, colorado, was the site of a st. louis encephalitis (sle) outbreak in 1985. epidemiologic and ecologic investigations in 1985 and 1986 suggested that culex tarsalis may not have been the exclusive vector in the outbreak and that cx. pipiens may have contributed to transmission as an accessory vector. a limited field study in 1987 generally confirmed observations from 1986 that cx. pipiens was more abundant than cx. tarsalis in late summer when sle virus transmission normally occur ... | 1989 | 2746202 |
| vertical transmission of st. louis encephalitis virus to autogenously developed eggs of aedes atropalpus mosquitoes. | vertical transmission of st. louis encephalitis virus was demonstrated by a strain of aedes atropalpus mosquitoes from garrett county, md. five-day-old parental females containing fully formed autogenous eggs were infected by intrathoracic inoculation. st. louis encephalitis virus was detected in batches of fertilized eggs and fourth instar larvae. estimated filial infection rates of approximately 1% were observed for both eggs and larvae. | 1990 | 2098473 |
| venereal transmission of st. louis encephalitis virus by culex quinquefasciatus males (diptera: culicidae). | uninfected, virgin, colonized culex quinquefasciatus say females became infected when caged with males that had been infected with st. louis encephalitis (sle) virus by inoculation. when these females were assayed 7 or 28 d after first exposure to infected males, 23% and 25%, respectively, were infected with sle virus. fifty-eight percent (n = 83) of the inseminated females were infected with sle virus, whereas only 23% (n = 23) of virgin females were infected. these data show that at least some ... | 1990 | 2159075 |
| temporal variations in the susceptibility of a semi-isolated population of culex tarsalis to peroral infection with western equine encephalomyelitis and st. louis encephalitis viruses. | a semi-isolated population of culex tarsalis in kern county, ca was found to vary significantly in its seasonal and yearly susceptibility to peroral infection with western equine encephalomyelitis (wee) and st. louis encephalitis (sle) viruses during the breeding seasons of 1975-1981. female cohorts of the population were significantly more resistant to wee virus from 1975 through 1977 than from 1978 through 1981. on the average, females were 40 times more susceptible to wee virus during may tha ... | 1990 | 2160200 |
| diel changes in adult mosquito microhabitat temperatures and their relationship to the extrinsic incubation of arboviruses in mosquitoes in kern county, california. | microhabitat temperatures experienced by nocturnally active culex tarsalis coquillett mosquitoes were measured in the southern san joaquin valley of california. temperatures of the diurnal resting shelter and nocturnal activity air space were measured by digital recorder at three cx. tarsalis habitats in kern county. temperatures measured by digital recorders agreed well with temperatures recorded concurrently at nearby california irrigation management and inspection system weather stations. mon ... | 1990 | 2167374 |
| low ph-induced cell fusion in flavivirus-infected aedes albopictus cell cultures. | cell-to-cell fusion of aedes albopictus (mosquito) cells infected with dengue and st louis encephalitis (sle) flaviviruses was induced by exposure to low ph. the parameters of this low ph-induced fusion were examined. syncytium formation was maximal in cultures 36 to 48 h post-infection and occurred when cultures were maintained at the acid ph for 15 min at 35 degrees c. the optimal ph range for fusion was 5.0 to 6.5 for dengue virus-infected cells and 5.0 to 5.5 for sle virus-infected cells. sy ... | 1990 | 2167941 |
| mosquito bionomics and the lack of arbovirus activity in the chino area of san bernardino county, california. | mosquito bionomics, including temporal abundance, metabolic status, and blood-feeding patterns, and arbovirus activity were studied at representative dairy and residential habitats in chino, calif., during 1987 and 1988. host-seeking culex tarsalis coquillett and cx. quinquefasciatus say females were more abundant and appeared earlier each season at traps near dairy breeding sources than at traps in residential areas, whereas cx. stigmatosoma dyar, which also breeds in dairy effluent, was most a ... | 1990 | 2231618 |
| persistence of mosquito-borne viruses in kern county, california, 1983-1988. | the persistence of arboviruses was studied from 1983 to 1988 in mixed agriculture, marsh, riparian, and foothill habitats in kern county, ca. western equine encephalomyelitis (wee) virus was isolated frequently during 1983 from culex tarsalis and aedes melanimon and was detected by the seroconversion of sentinel chickens. wee virus then disappeared, even though vector competence studies during 1984-1986 showed that cx. tarsalis was able to transmit wee virus. st. louis encephalitis (sle) virus w ... | 1990 | 2240370 |
| effect of the anesthetizing agent triethylamine on western equine encephalomyelitis and st. louis encephalitis viral titers in mosquitoes (diptera: culicidae). | triethylamine (tea) is a chemical compound that provides an effective means to anesthetize mosquitoes. the mosquitoes remain alive but are incapacitated for several hours; they do not recover following treatment. there was no effect on the titers of infectious virus recovered from western equine encephalomyelitis or st. louis encephalitis virus-infected culex tarsalis coquillett and aedes dorsalis (meigen) that were anesthetized with tea prior to storage at -70 degrees c. furthermore, tea had no ... | 1990 | 2280383 |
| rainfall-directed oviposition behavior of culex nigripalpus (diptera: culicidae) and its influence on st. louis encephalitis virus transmission in indian river county, florida. | resting culex nigripalpus theobald were collected with a ground aspirator three times a week in indian river county, fla., from january 1985 through december 1987. the number of green (newly emerged), empty, blood-fed, and gravid females in each collection was counted; up to 100 empty females were dissected to estimate the abundance of empty, parous females in the population. in general, this species was uncommon during the dry season from january through june but increased during the wet season ... | 1990 | 2299655 |
| experimental studies to determine the susceptibility to infection with st. louis encephalitis virus of five species of panamanian mosquitoes. | the susceptibility to infection with a panamanian isolate of st. louis encephalitis (sle) virus was evaluated in culex quinquefasciatus, haemagogus equinus, mansonia dyari, sabethes cyaneus and deinocerites pseudes. when fed on blood-virus suspensions using the hanging drop or pledget technique, the median infective dose (id50) of sle virus for colonized strains of cx. quinquefasciatus and hg. equinus was 10(2.8) plaque forming units (pfu)/2 microliters and 10(3.5) pfu/2 microliters, respectivel ... | 1991 | 1686273 |
| distribution of st. louis encephalitis viral antibody in sentinel chickens maintained in sarasota county, florida: 1978-1988. | sentinel chicken flocks monitored arboviral transmission at 12 sites in sarasota county, fla., from 1978 through 1988. during this time, 3,452 serum samples were analyzed for hemagglutination inhibition antibody to st. louis encephalitis virus (sle) and eastern equine encephalomyelitis virus (eee). overall, 91 chickens seroconverted to sle and three to eee. the intensity of sle transmission showed considerable year-to-year variation. chickens from south-county flocks were more likely to seroconv ... | 1991 | 2033613 |
| preliminary studies of aedes bahamensis as a host and potential vector of st. louis encephalitis virus. | aedes bahamensis, a recent introduction to the state of florida, was studied to determine its capability to serve as a host or vector of st. louis encephalitis (sle) virus. females were readily infected by inoculation, and had whole body virus titers as high as 10(9.4) mosquito infectious doses 50. sixty percent of females that had been infected by inoculation were capable of orally transmitting virus. nearly half of the females feeding on viremic chickens became infected, but not all of these i ... | 1991 | 2045810 |
| use of the polymerase chain reaction for the sensitive detection of st. louis encephalitis viral rna. | polymerase chain reaction (pcr) assays were developed for the detection of rna from the st. louis encephalitis (sle) virus. using computer-assisted analysis of the msi-7 strain sle virus genome, two primer pairs were selected from the capsid-coding and the membrane associated protein-coding genes, and one from the envelope-coding gene. reverse transcription was primed with either specific oligomers or with random hexamers; these methods were compared for cdna synthesis and subsequent pcr amplifi ... | 1992 | 1348060 |
| mosquito and arbovirus ecology in southeastern california, 1986-1990. | mosquito abundance and western equine encephalomyelitis (wee) and st. louis encephalitis (sle) virus activity were monitored in five valleys in southeastern california from june 1986 through april 1990 to study virus overwintering and possible dissemination from south to north along geographically defined corridors. culex tarsalis coquillett predominated in co2 trap collections and was the only species repeatedly infected with wee and sle viruses. abundance peaked during april-may and august-oct ... | 1992 | 1352557 |
| virus-dependent mortality in rift valley fever, eastern equine encephalomyelitis, and chikungunya virus-inoculated mosquito (diptera: culicidae) larvae. | the effect of inoculation of mosquito larvae with rift valley fever (rvf) virus on survival to the adult stage was evaluated in aedes aegypti (l.), ae. fowleri (charmoy), ae. mcintoshi huang, ae. taeniorhynchus (wiedemann), ae. triseriatus (say), eretmapodites quinquevittatus theobald, anopheles albimanus wiedemann, and culex pipiens l. pupation rates were similar for rvf virus-inoculated and diluent-inoculated larvae of all mosquito species tested except cx. pipiens. however, with the exception ... | 1992 | 1357176 |
| detection of st. louis encephalitis virus in mosquitoes by use of the polymerase chain reaction. | we recently developed an assay using the polymerase chain reaction (pcr) for the specific detection of st. louis encephalitis (sle) virus rna. this assay was tested in a blind study on 7 samples of pooled mosquitoes (50 mosquitoes/pool) which were also characterized for sle virus by plaque assay in vero cell culture. one sample was positive for the sle virus as determined by both the pcr assay and a combination of the plaque assay and the indirect fluorescent antibody assay. the remaining 6 samp ... | 1992 | 1383418 |
| experimental inoculation of three arboviruses in black-bellied whistling ducks (dendrocygna autumnalis). | wild-caught, immature black-bellied whistling ducks (dendrocygna autumnalis) were inoculated with eastern equine encephalitis (eee), st. louis encephalitis (sle), or western equine encephalitis (wee) virus. susceptibility, duration and titer of viremia, and antibody response to these arboviruses were determined. birds from all inoculated groups became viremic. higher virus titers occurred in the eee group but overall mean titers were not significantly different among experimental groups. all bir ... | 1992 | 1474647 |
| ecology of mosquitoes and st. louis encephalitis virus in the los angeles basin of california, 1987-1990. | st. louis encephalitis (sle) virus has become established in the los angeles basin of california, where it most likely is maintained by horizontal transmission among culex tarsalis coquillet and passerine birds in park-riparian habitat. viral transmission also was detected at low levels in residential habitat by the infrequent seroconversion of sentinel chickens. sle virus activity was documented in all months except march and april. cx. tarsalis was incriminated as the primary vector, based on ... | 1992 | 1495066 |
| evaluation of domestic pigeons as sentinels for detecting arbovirus activity in southern california. | flocks of sentinel domestic pigeons (columbia livia) detected increases in st. louis encephalitis (sle) and western equine encephalomyelitis (wee) virus activity in southern california concurrently with flocks of sentinel chickens. however, occasional low-titered, transient seroconversions to both wee and sle viruses also occurred in pigeons during periods when virus activity was not detected by seroconversions in sentinel chickens, by virus isolation from culex mosquitoes, or by human disease. ... | 1992 | 1536386 |
| ecological observations on the 1989 outbreak of st. louis encephalitis virus in the southern san joaquin valley of california. | temporal and spatial patterns of st. louis encephalitis (sle) virus transmission were compared at permanent study areas in the southern san joaquin valley during years with low (1988 and 1990) and elevated (1989) viral activity. during 1989 and 1990, virus appeared first at sentinel chicken flocks exhibiting low to moderate seroconversion rates at the end of the previous season. this finding, and the early season seroconversion of sentinel chickens at a marsh habitat on 5 march and 2 april 1990, ... | 1992 | 1625296 |
| molecular and biological characterization of a non-glycosylated isolate of st louis encephalitis virus. | the glycosylation patterns of the envelope (e) glycoprotein of several naturally occurring strains of st louis encephalitis (sle) virus were investigated. sle viruses were found that contained both glycosylated and non-glycosylated e proteins, and one isolate (tr 9464) that lacks n-linked glycosylation sites on its e protein was identified. sle virus monoclonal antibodies that define e protein b cell epitopes and demonstrate biological activities reacted essentially to the same extent with glyco ... | 1993 | 7506301 |
| st louis encephalitis virus establishes a productive, cytopathic and persistent infection of sf9 cells. | the sf9 cell line, commonly used for gene expression by recombinant baculovirus, has been productively infected by st louis encephalitis (sle) virus, a flavivirus. sle viral infection produced a c.p.e. in the sf9 cells characterized by giant cells and the presence of 10-fold fewer cells in the infected cultures after the first week of infection compared with uninoculated control cultures. infected sf9 cells expressed sle viral antigens, and intracellular virus particles were observed by electron ... | 1993 | 8345362 |
| epidemiologic aspects of a st. louis encephalitis epidemic in jefferson county arkansas, 1991. | in 1991, the first epidemic of st. louis encephalitis (sle) ever reported in arkansas resulted in 25 cases in pine bluff (attack rate: 44 per 100,000; 95% confidence interval [ci] 28-65). to identify risk factors for sle viral infection and risk factors for neuroinvasive illness, we conducted a community-based, cross-sectional study of noninfected and asymptomatically infected persons and a case-control study of asymptomatically and symptomatically infected persons. the sle viral infection rate ... | 1993 | 8352389 |
| entomologic investigations of an epidemic of st. louis encephalitis in pine bluff, arkansas, 1991. | an epidemic of st. louis encephalitis (sle) occurred in jefferson county, arkansas during july-august 1991. at least 26 human cases were involved, with 25 cases in the town of pine bluff. twelve isolates of sle virus were obtained from mosquitoes collected in pine bluff between august 13 and 24: 11 from pools of culex pipiens quinquefasciatus, resulting in a minimum infection rate of 1.6 per 1,000 (n = 6,768) for this subspecies, and one isolate from a pool of 22 mosquitoes identified as cx. (cu ... | 1993 | 8352390 |
| avian hosts of st. louis encephalitis virus in pine bluff, arkansas, 1991. | an investigation of the extent of st. louis encephalitis (sle) virus activity in the avian population in pine bluff, arkansas was conducted from august 30, 1991 through september 5, 1991, following an sle epidemic that resulted in 25 human cases. a total of 363 birds of 33 species were captured with ground-level mist nets at four sites along the northern edge of the city. no viruses were isolated from the serum of these birds, but 91 birds (25%) of 11 species had detectable neutralizing antibody ... | 1993 | 8352391 |
| effect of temperature on the transmission of western equine encephalomyelitis and st. louis encephalitis viruses by culex tarsalis (diptera: culicidae). | the extrinsic incubation rate (inverse of the time in days from infection to median transmission) of western equine encephalomyelitis (wee) and st. louis encephalitis (sle) viruses by laboratory strains of culex tarsalis coquillett increased as a linear function of incubation temperatures from 10 to 30 degrees c. the estimated temperatures for zero transmission thresholds (intercept of the x axis) were 10.9 and 14.9 degrees c, and the number of degree days above these thresholds required for med ... | 1993 | 8433322 |
| arbovirus surveillance in northern colorado, 1987 and 1991. | arbovirus surveillance was conducted during an epizootic of western equine encephalitis (wee) during 1987 and during a nonepizootic year, 1991, in the same area in northern colorado. mosquitoes were collected in larimer county, co, during weeks 33-37 (10 august to 7 september) in 1987 and during weeks 26-35 (24 june to 26 august) in 1991. in total, 13,099 mosquitoes in 694 pools collected during 1987 and 8,672 mosquitoes in 242 pools collected during 1991 were tested for virus. wee virus was iso ... | 1993 | 8433334 |
| [the relationship between mosquito vectors and aquatic birds in the potential transmission of 2 arboviruses]. | the authors studied for two years the role of the chicks of aquatic birds in the arboviral cycles in coastal lagoons in central panama in order to determine the relation between culex (melanoconion) ocossa and mansonia (mansonia) dyari mosquitoes in the transmission and dissemination of the viruses of saint louis encephalitis (sle) and venezuelan equine encephalitis (vee). mosquitoes were captured every fifteen days on two consecutive nights to isolate the virus, using light traps (cdc) and bait ... | 1993 | 8101009 |
| isolation of st. louis encephalitis virus from a killer whale. | we report the isolation of st. louis encephalitis (sle) virus from a mature male killer whale (orcinus orca). this represents the first isolation of sle virus from a marine mammal. the animal presented with reduced appetite, rapidly became lethargic and subsequently died. virus-induced cpe was observed in a dolphin cell line, sp-1k (atcc ccl 78), inoculated with brain, kidney, and lung tissues obtained at necropsy. electron microscopy of infected sp-1k cells revealed the presence of virions havi ... | 1993 | 15566723 |
| epidemiologic aspects of a st. louis encephalitis outbreak in fort walton beach, florida in 1980. | from july 10 through august 4, 1980, five cases of st. louis encephalitis (sle) occurred in and near fort walton beach on the gulf coast of northwest florida. these were the first cases of sle ever reported from the florida panhandle. to determine the extent of sle infection in the community, sera (n = 968) were collected from patients at the local hospital and county public health unit and tested for sle virus antibody. the sle attack rate was highest in a centrally located impoverished census ... | 1994 | 8147497 |
| vector competence of aedes albopictus from pine bluff, arkansas, for a st. louis encephalitis virus strain isolated during the 1991 epidemic. | the vector competence of aedes albopictus from pine bluff, ar, was assessed for a st. louis encephalitis (sle) virus strain isolated during the 1991 epidemic. aedes albopictus were fed on hamsters with viremia levels of 10(4.6)-10(4.9) vero cell plaque-forming units (pfu)/ml. at 7 and 15 days postbloodfeeding, transmission trials were conducted using individual suckling mice. three of 313 ae. albopictus were determined to be infected with sle virus with titers of 10(6.3)-10(7.0) pfu/mosquito. at ... | 1994 | 7707054 |
| comparison of chickens and pheasants as sentinels for eastern equine encephalitis and st. louis encephalitis viruses in florida. | pheasants and chickens were compared as sentinels for monitoring the transmission of arboviruses of public health significance in florida during 1991-93. results suggest that pheasants are better sentinels for eastern equine encephalitis (eee) virus. they detected virus transmission 3-6 weeks earlier in epizootic years, 2-4 times more frequently during the season, and twice as many birds within a flock seroconverted during a given week. pheasants detected virus transmission at 2 sites during 2 i ... | 1994 | 7707062 |
| viremia and serological responses in adult chickens infected with western equine encephalomyelitis and st. louis encephalitis viruses. | adult hens, similar to those used for arbovirus surveillance, were experimentally infected with western equine encephalomyelitis (wee) and st. louis encephalitis (sle) viruses to describe the viremia response, to compare serological testing methods, and to evaluate a new method of collecting whole blood onto filter paper strips from lancet pricks of the chicken comb. young (19 weeks), but not old (38 weeks), hens developed a low-titer, transient viremia for a 1-day period. immunoglobulin g (igg) ... | 1994 | 7707063 |
| arboviruses in water birds (ciconiiformes, pelecaniformes) from florida. | sera from 360 ciconiform and pelecaniform birds collected in florida (usa) from 1974 to 1990 were tested for serum neutralizing (sn) antibodies to eastern equine encephalitis (eee), st. louis encephalitis (sle), and everglades (eve) viruses. serum neutralizing antibodies to eee virus were detected in 2%, to sle virus in 7%, and to eve virus in none of the samples. pelecaniform birds (16%) had a higher antibody prevalence (p < 0.02) for sle virus than did ciconiform birds (5%). virus could not be ... | 1994 | 8028106 |
| potential effect of global warming on mosquito-borne arboviruses. | if global warming occurs in california, daily mean temperatures may increase by 3 to 5 degrees c, precipitation patterns will change, and sea level may rise 1 m. studies were done on effect of temperature changes on survival of culex tarsalis coquillett, the primary vector of western equine encephalomyelitis (wee) and st. louis encephalitis (sle) viruses, in two regions where temperatures differed by 5 degrees c. daily mortality of adult vectors increased by 1% for each 1 degree c increase in te ... | 1994 | 8057305 |
| an integrated target sequence and signal amplification assay, reverse transcriptase-pcr-enzyme-linked immunosorbent assay, to detect and characterize flaviviruses. | we previously described a reverse transcriptase-pcr using flavivirus genus-conserved and virus species-specific amplimers (d. w. trent and g. j. chang, p. 355-371, in y. becker and c. darai; ed., frontiers of virology, vol. 1, 1992). target amplification was improved by redesigning the amplimers, and a sensitive enzyme-linked immunosorbent assay (elisa) technique has been developed to detect amplified digoxigenin (dig)-modified dna. a single biotin motif and multiple dig motifs were incorporated ... | 1994 | 7512096 |
| antibodies to st. louis encephalitis virus in armadillos from southern florida. | from january 1990 through march 1991, 189 armadillos (dasypus novemcinctus) were collected from brevard and glades counties in southern florida (usa). the sera were analyzed for hemagglutination-inhibition (hai) antibodies against st. louis encephalitis (sle) and eastern equine encephalomyelitis (eee) viruses. none of the armadillos had detectable hai antibody to eee virus, but 59 (31%) had antibodies against sle virus. sera from 31 of the hai-positive armadillos contained significant levels of ... | 1995 | 7563416 |
| landscape ecology of arboviruses in southern california: temporal and spatial patterns of vector and virus activity in coachella valley, 1990-1992. | consistent temporal and spatial patterns in the activity of culex tarsalis coquillett and western equine encephalomyelitis (wee) and st. louis encephalitis (sle) viruses were delineated that were useful in developing a stratified surveillance program. vernal increases in cx. tarsalis abundance typically were associated with flooding of saline marshes along the north shore of the salton sea and were followed 6-8 wk later by the onset of wee and sle virus activity. viruses then spread to managed m ... | 1995 | 7616515 |
| landscape ecology of arboviruses in southern california: patterns in the epizootic dissemination of western equine encephalomyelitis and st. louis encephalitis viruses in coachella valley, 1991-1992. | temporal and spatial patterns in the initiation and dissemination of western equine encephalomyelitis and st. louis encephalitis virus activity in coachella valley during 1991 and 1992 were detected by testing pools of host-seeking culex tarsalis coquillett for virus infection and sentinel chickens for seroconversions. both viruses repeatedly were detected first at a salt marsh adjacent to the salton sea in the southeastern corner of the study area and then disseminated to the northwest to fresh ... | 1995 | 7616516 |
| development of a species-diagnostic polymerase chain reaction assay for the identification of culex vectors of st. louis encephalitis virus based on interspecies sequence variation in ribosomal dna spacers. | culex pipiens complex mosquitoes (cx. p. pipiens and cx. p. quinquefasciatus) are among the principal vectors of st. louis encephalitis (sle) virus in the eastern united states; cx. restuans and cx. salinarius play secondary roles in the transmission and maintenance of the virus cycle. accurate identification of these three species in field collections is required for epidemiologic studies of sle virus transmission. we have developed a polymerase chain reaction (pcr) assay for this purpose. spec ... | 1995 | 7625528 |
| nonvascular delivery of st. louis encephalitis and venezuelan equine encephalitis viruses by infected mosquitoes (diptera: culicidae) feeding on a vertebrate host. | we determined whether mosquitoes infected with the viruses st. louis encephalitis (sle) or venezuelan equine encephalitis inoculate virus extravascularly or directly into the vascular system. infected mosquitoes fed on the distal 3rd of the tails of suckling mice. significantly more mice whose tails were amputated at the midpoint within 10 min of mosquito feeding survived than did siblings whose tails remained intact. even when tails were amputated 1-6 h after sle virus-infected mosquitoes fed, ... | 1995 | 7650720 |
| studies on mosquitoes (diptera: culicidae) and anthropic environment. 10- survey of adult behaviour of culex nigripalpus and other species of culex (culex) in south-eastern brazil. | a survey of adult behaviour of culex (culex) species was carried out from august 1992 through december 1993 in a human modified (anthropic) environment in the ribeira valley, s. paulo state, brazil. culex nigripalpus dominated the catches at several sites and it's tendency to increase in the anthropic environment became quite clear. nevertheless no high level of synanthropy was demonstrated. so it seems that the mosquito may have a restricted role in natural arbovirus cycles. nonetheless, cx. ni ... | 1995 | 8729276 |
| mosquito productivity and surveillance for st. louis encephalitis virus in chicago during 1993. | the city of chicago's department of health monitors weekly deposition of egg rafts of culex species, prevalence of st. louis encephalitis (sle) virus-specific antibodies in feral birds, and prevalence of the virus in mosquito pools. the total number of culex egg rafts collected in 1993 (4,623) was 2-fold greater than for the 1992 mosquito season. virtually all of the early summer egg rafts were identified as culex restuans. after the week of july 18, culex pipiens accounted for 20-70% of the tot ... | 1995 | 8551297 |
| immunity to st. louis encephalitis virus by sequential immunization with recombinant vaccinia and baculovirus derived prm/e proteins. | st. louis encephalitis (sle) is an important mosquito-borne disease of great public health concern in parts of the united states. south america and canada. protective immunogens of flaviviruses produced in different expression systems have been shown to be effective against virulent virus infection in laboratory animal models. here we show that the pre-membrane and envelope (prm/e) of sle virus expressed in insect and mammalian cell systems using baculovirus and vaccinia virus, respectively, are ... | 1995 | 8525682 |
| search for viral nucleic acid sequences in brain tissues of patients with schizophrenia using nested polymerase chain reaction. | we used polymerase chain reaction to search for nucleic acid sequences of several viruses in dna and rna extracted from brain tissues of schizophrenic and control subjects. | 1996 | 8540775 |
| immunisation with dna polynucleotides protects mice against lethal challenge with st. louis encephalitis virus. | in vivo transfection by intramuscular injection with plasmids expressing the immunogenic proteins of microbial pathogens has considerable potential as a vaccination strategy against many pathogens of both man and animals. here we report that weanling mice given a single intramuscular injection of 50 micrograms of a plasmid, psle1 expressing the st. louis encephalitis virus (sle) prm/e protein under the control of the cytomegalovirus immediate early protein promoter produced sle-specific antibody ... | 1996 | 8645110 |
| seasonal variation in the vector competence of culex tarsalis (diptera:culicidae) from the coachella valley of california for western equine encephalomyelitis and st. louis encephalitis viruses. | the vector competence of culex tarsalis coquillett from the coachella valley of california for western equine encephalomyelitis (wee) and st. louis encephalitis (sle) viruses was monitored monthly from february to november 1993. the concentration of wee virus required to infect 50% of the females increased during summer coincidentally with ambient temperature and was highest during july. transmission rates of wee virus were high during march, low during may-june, and high again during july-septe ... | 1996 | 8667391 |