characterization of a new marburg virus isolated from a 1987 fatal case in 1987, an isolated case of fatal marburg disease was recognized during routine clinical haemorrhagic fever virus surveillance conducted in kenya. this report describes the isolation and partial characterization of the new marburg virus (strain ravn) isolated from this case. the ravn isolate was indistinguishable from reference marburg virus strains by cross-neutralization testing. virus particles and aggregates of marburg nucleocapsid matrix in ravn-infected vero cells, were visualized by immu ...19968800792
experimental infection of cynomolgus macaques with ebola-reston filoviruses from the 1989-1990 u.s. epizootic.this study describes the pathogenesis of the ebola-reston (ebo-r) subtype of ebola virus for experimentally infected cynomolgus monkeys. the disease course of ebo-r in macaques was very similar to human disease and to experimental diseases in macaques following ebo-zaire and ebo-sudan infections. cynomolgus monkeys infected with ebo-r in this experiment developed anorexia, occasional nasal discharge, and splenomegaly, petechial facial hemorrhages and severe subcutaneous hemorrhages in venipunctu ...19968800793
are all diseases infectious?the complex interactions between microorganisms and human hosts include the well-known, traditional infectious diseases and the symbiotic relation we have with our normal flora. the media have brought to the public's attention many newly described infectious diseases, such as ebola virus hemorrhagic fever, that were not part of common medical parlance a decade ago. while flooding us with interesting and often dramatic reports of so-called emerging infectious diseases, the media have largely igno ...19968928993
[developing principles for emergency prevention and treatment of ebola fever].the authors validate the efficiency of pathogenetic approach to the development of urgent measures for the prevention and therapy of ebola fever. the virus circulating in the body is to be blocked as soon as possible and the impaired functions and systems repaired. therapy of ebola fever should be based on the earliest possible and sufficiently prolonged administration of specific immunoglobulins in combination with pathogenetic drugs.19979103042
the thucydides syndrome: ebola déjà vu? (or ebola reemergent?) 19968964060
[development of the immunoenzyme test-system for detection of ebola virus antigen].an enzyme immunoassay system has been developed for the detection of ebola virus antigen. it permits a highly accurate and sensitive rapid detection of the antigen. optimal dilutions of specific immunoglobulin (1:500, corresponding to protein concentration of 50 micrograms/ml) and conjugate were found. the resolving capacity of the new test system is 1.9 x 10(-7) g protein.19968967072
occupationally acquired infections in health care workers. part care workers are at occupational risk for a vast array of infections that cause substantial illness and occasional deaths. despite this, few studies have examined the incidence, prevalence, or exposure-associated rates of infection or have considered infection-specific interventions recommended to maintain worker safety.19968967673
ebola haemorrhagic fever. a summary of the outbreak in gabon. 19979002779
[ebola: "a fatal syndrome"].no other clinical entity has attached more attention now-a-day than those precipitated by the infection with a hemorrhagic fever virus. potentially caused by arena, bunya, flavi, and filoviradae, only the latter has had such a major impact throughout the world. two major genuses have been recognized since they become evident for the first time in 1967, the single-species marburg, and the 3-species-ebola (e. zaire, sudan and reston). with the exception of the 2 outbreaks of e. reston (washington, ...19969004731
computer simulations of proteolysis of marburg and ebola-zaire filovirus coded proteins to generate nonapeptides with motifs of known hla class i haplotypes and detection of antigenic domains in the viral glycoproteins.the primary amino acid sequences of the proteins coded by marburg and ebola-zaire filoviruses were studied by computer programs to search for putative proteolytic cleavages which yield nonapeptides with motifs of binding to known hla class i haplotypes. the computer analyses predicted that numerous nonapeptides with motifs to bind hla class i a68 and a2 haplotypes were detected. a few nonapeptides with motifs hla class i a24, b8, b27 and b35 were predicted in marburg virus proteins. a similar fi ...19969035363
[change in biochemical and hemostatic indicators in guinea pigs upon administering ebola virus preparations].the biochemical and hemostatic parameters were compared in guinea pigs after inoculation of ebola virus strains lethal and nonlethal for them and of inactivated antigen of this virus. the time course of the main hemostatic and biochemical parameters in animals challenged with the lethal strain of ebola virus differed much from that in other groups. this permits us to hypothesize that modification of the virus in the course of adaptation to the host results in the appearance of properties boostin ...19979304298
isolation and partial molecular characterisation of a strain of ebola virus during a recent epidemic of viral haemorrhagic fever in gabon. 19979111552
[viral haemorrhagic fever].viral haemorrhagic fever denotes various kinds of febrile illness caused by certain viruses which often presents with bleeding tendency and occasionally shock. out of these, the four maladies, lassa fever, ebola haemorrhagic fever, marburg haemorrhagic fever and crimean-congo haemorrhagic fever which are endemically present in africa or eastern europe, are known to be such diseases with high man-to-man communicability. these four haemorrhagic fevers are, therefore, designated as special conditio ...19979283226
summary of antibody workshop: the role of humoral immunity in the treatment and prevention of emerging and extant infectious the era before antibiotics, human diseases were commonly treated with immune animal and human sera, often with life-saving results. with the advent of emerging infectious diseases, many of which cannot be adequately treated or prevented, attempts to develop antibody treatments have taken on new importance. the role of humoral immunity in treatment and prevention was the focus of discussion at a 1996 workshop. the cellular and molecular mechanisms of neutralization were examined in detail. it ...19979291299
[immunobiological properties of vp24 protein of ebola virus expressed by recombinant vaccinia virus].immunological and biochemical parameters were studied in guinea pigs immunized with recombinant vaccinia virus containing full-sized gene of ebola virus vp24 protein and then infected with virulent strain of ebola virus. the majority of the studied parameters changed similarly in guinea pigs immunized with recombinant vaccinia virus and control guinea pigs inoculated with vaccinia virus both before and after challenge with ebola virus. however, in animals immunized with recombinant vaccinia viru ...19979297340
identification of the ebola virus in gabon in 1994. 19979111553
isolation and phylogenetic characterization of ebola viruses causing different outbreaks in gabon.three outbreaks of ebola hemorrhagic fever have recently occurred in gabon. virus has been isolated from clinical materials from all three outbreaks, and nucleotide sequence analysis of the glycoprotein gene of the isolates and virus present in clinical samples has been carried out. these data indicate that each of the three outbreaks should be considered an independent emergence of a different ebola virus of the zaire subtype. as in earlier ebola virus outbreaks, no genetic variability was dete ...19979126445
computational genomic analysis of hemorrhagic fever viruses. viral selenoproteins as a potential factor in pathogenesis.a number of distinct viruses are known as hemorrhagic fever viruses based on a shared ability to induce hemorrhage by poorly understood mechanisms, typically involving the formation of blood clots ("disseminated intravascular coagulation"). it is well documented that selenium plays a significant role in the regulation of blood clotting via its effects on the thromboxane/prostacyclin ratio, and effects on the complement system. selenium has an anticlotting effect, whereas selenium deficiency has ...19979152513
phosphatidylinositol-dependent membrane fusion induced by a putative fusogenic sequence of ebola virus.the membrane-interacting abilities of three sequences representing the putative fusogenic subdomain of the ebola virus transmembrane protein have been investigated. in the presence of calcium, the sequence ebo(ge) (gaaiglawipyfgpaae) efficiently fused unilamellar vesicles composed of phosphatidylcholine, phosphatidylethanolamine, cholesterol, and phosphatidylinositol (molar ratio, 2:1:1:0.5), a mixture that roughly resembles the lipid composition of the hepatocyte plasma membrane. analysis of th ...19989499027
[study of the phagocytic ability of blood polymorphonuclear leukocytes from rabbits and guinea pigs upon administering ebola virus].study of the phagocytic activity of polymorphonuclear leukocytes (pmnl) of rabbits resistant to ebola virus and guinea pigs susceptible to it, repeatedly challenged with live or inactivated ebola virus in accordance with the immunization protocols, showed a much higher phagocytic activity in animals resistant to the virus than in those susceptible to it. such behavior of pmnl in guinea pigs may be explained by the absence of the necessary cytokine background activating the neutrophils.19979182399
[false-positive reactions in laboratory diagnosis of lassa, marburg, and ebola viral hemorrhagic fevers and aids].sera of normal subjects and aids patients living in minsk and odessa were tested for antibodies to hazardous viral infections lassa, marburg, and ebola. four to 16% of examinees were seropositive to ebola virus, 0.8 to 2.3% to lassa, and up to 0.8% to marburg virus. common b-epitopes were found in viruses belonging to different families: lassa, ebola, and hiv. antibodies specific to these viruses antigens were found in the reference sera to influenza a and b, respiratory syncytial virus, and ade ...19979182402
processing of the ebola virus glycoprotein by the proprotein convertase the present study, we have investigated processing and maturation of the envelope glycoprotein (gp) of ebola virus. when gp expressed from vaccinia virus vectors was analyzed by pulse-chase experiments, the mature form and two different precursors were identified. first, the endoplasmic reticulum form pregper, full-length gp with oligomannosidic n-glycans, was detected. pregper (110 kda) was replaced by the golgi-specific form pregp (160 kda), full-length gp containing mature carbohydrates. p ...19989576958
[effect of inactivated ebola virus on colony forming activity of human hematopoietic stem cells].the effect of ebola virus antigen on the growth of hemopoietic precursors was studied. incubation of mononuclear cells with the viral antigen led to a dose-dependent decrease of erythroid colony formation but did not alter the growth of the granulocyto-macrophagal precursors. hence, ebola virus antigen is capable of directly affecting the hemopoietic activity of precursors in man by inhibiting the growth of erythroid colonies.19979182409
[changes in certain indicators of hemostasis in rabbits upon administration of ebola virus preparations].changes in some parameters of hemostasis in rabbits insusceptible to ebola virus (ev) in various periods after reinoculations with live and inactivated virus are described. challenge with both control protein and live and inactivated ev leads to imbalance in the hemostasis system, which is compensated for in the course of follow-up and does not result in clinically manifest disorders of blood clotting. however, the mechanisms of development of the hemostasis imbalance caused by the control prote ...19979297348
global aspects of emerging and potential zoonoses: a who perspective.many new human pathogens that have emerged or reemerged worldwide originated from animals or from products of animal origin. many animal species as well as categories of agents have been involved in the emergence of diseases. wild (e.g., bats, rodents) as well as draught animals (e.g., horses) and food animals (e.g., poultry, cattle) were implicated in the epidemiologic cycles of these diseases. many of the agents responsible for new infections and diseases in humans were viruses (e.g., hantavir ...19979204308
the origin and evolution of ebola and marburg viruses.molecular evolutionary analyses for ebola and marburg viruses were conducted with the aim of elucidating evolutionary features of these viruses. in particular, the rate of nonsynonymous substitutions for the glycoprotein gene of ebola virus was estimated to be, on the average, 3.6 x 10(-5) per site per year. marburg virus was also suggested to be evolving at a similar rate. those rates were a hundred times slower than those of retroviruses and human influenza a virus, but were of the same order ...19979254917
[virus transmission in the tropical environment, the socio-ecology of primates and the balance of ecosystems].we studied the contribution of non human primates to the transmission of yellow fever and hiv in the wild. we demonstrate the consequences of the modification of ecosystems on the emergence of new viral diseases and the reappearance of diseases believed to be eradicated. in the primary forest, the natural yellow fever cycle is limited to monkeys and mosquitoes living high in the canopy. transmission to man is an anomaly, requiring the circumstances found in the forest and savanna contact zones, ...19979273125
[methods for controlling colonization of air and laboratory surfaces by pathogens of certain especially dangerous viral infections].regular check-ups of the laboratory environment (air and working surfaces) for contamination with the objects of investigations are obligatory for laboratories working with viruses causing grave diseases, such as ebola, marburg, and machupo fevers and venezuelan equine encephalomyelitis. methods for indication and identification of these agents have been developed and experimentally tried.19979304303
international colloquium on ebola virus research: summary report. 19979333167
ebola and hantaviruses. 19979348164
experimental inoculation of plants and animals with ebola virus.thirty-three varieties of 24 species of plants and 19 species of vertebrates and invertebrates were experimentally inoculated with ebola zaire virus. fruit and insectivorous bats supported replication and circulation of high titers of virus without necessarily becoming ill; deaths occurred only among bats that had not adapted to the diet fed in the laboratory.19968969248
a system for functional analysis of ebola virus glycoprotein.ebola virus causes hemorrhagic fever in humans and nonhuman primates, resulting in mortality rates of up to 90%. studies of this virus have been hampered by its extraordinary pathogenicity, which requires biosafety level 4 containment. to circumvent this problem, we developed a novel complementation system for functional analysis of ebola virus glycoproteins. it relies on a recombinant vesicular stomatitis virus (vsv) that contains the green fluorescent protein gene instead of the receptor-bindi ...19979405687
emerging and reemerging infections. progress and challenges in the subspecialty of infectious disease pathology.emerging and reemerging infections are attracting greater attention from the public health and medical communities. pathologists and other physicians are increasingly aware of the importance of the subspecialty of infectious disease pathology as a tool for diagnosis, surveillance, and research of emerging infections. in this communication, we describe the role that infectious disease pathologists have played during the last 2 years in broadening our understanding of selected emerging infections, ...19979278604
pathology of experimental ebola virus infection in african green monkeys. involvement of fibroblastic reticular cells.ebola virus has been responsible for explosive lethal outbreaks of hemorrhagic fever in both humans and nonhuman primates. previous studies showed a predilection of ebola virus for cells of the mononuclear phagocyte system and endothelial cells.19979278608
[ultrastructural stereological analysis of monkey lungs during experimental ebola fever]. 19979280497
[study of the treatment-prophylactic effect of immunomodulators in experimental infections, caused by marburg, ebola, and venezuelan equine encephalitis viruses].therapeutic and prophylactic effects of immunomodifiers ridostin, reaferon, and polyribonate used alone and in various combinations were assessed in experiments on guinea pigs infected with venezuelan equine encephalomyelitis (vee) (strain trinidad), marburg (strain popp), and ebola (m/c-8 variant of zaire strain) viruses at doses 5 to 20 respiratory ld50 through the respiratory airways. urgent prophylactic simultaneous intramuscular and intranasal administration of ridostin protected the animal ...19979424849
ebola takes a punch. 19989427596
immunization for ebola virus infection.infection by ebola virus causes rapidly progressive, often fatal, symptoms of fever, hemorrhage and hypotension. previous attempts to elicit protective immunity for this disease have not met with success. we report here that protection against the lethal effects of ebola virus can be achieved in an animal model by immunizing with plasmids encoding viral proteins. we analyzed immune responses to the viral nucleoprotein (np) and the secreted or transmembrane forms of the glycoprotein (sgp or gp) a ...19989427604
variation in the glycoprotein and vp35 genes of marburg virus strains.marburg virus, the prototype of the family filoviridae, differs genetically, serologically, and morphologically from ebola viruses. to better define the genetic variation within the species, vp35 and glycoprotein (gp) genes of representative human isolates from four known episodes of marburg virus hemorrhagic fever were analyzed. the percentage nucleotide differences in the gp gene coding regions of marburg viruses (0.1-21%) was nearly equal to the percentage amino acid changes (0-23%), while th ...19989448698
ebola/athens revisited. 19989452412
distinct cellular interactions of secreted and transmembrane ebola virus glycoproteins.the mechanisms by which ebola virus evades detection and infects cells to cause hemorrhagic fever have not been defined, though its glycoprotein, synthesized in either a secreted or transmembrane form, is likely involved. here the secreted glycoprotein was found to interact with neutrophils through cd16b, the neutrophil-specific form of the fc gamma receptor iii, whereas the transmembrane glycoprotein was found to interact with endothelial cells but not neutrophils. a murine retroviral vector ps ...19989461435
endoproteolytic processing of the ebola virus envelope glycoprotein: cleavage is not required for function.proteolytic processing is required for the activation of numerous viral glycoproteins. here we show that the envelope glycoprotein from the zaire strain of ebola virus (ebo-gp) is proteolytically processed into two subunits, gp1 and gp2, that are likely covalently associated through a disulfide linkage. murine leukemia virions pseudotyped with ebo-gp contain almost exclusively processed glycoprotein, indicating that this is the mature form of ebo-gp. mutational analysis identified a dibasic moti ...19999882347
marburg hemorrhagic fever: report of a case studied by immunohistochemistry and electron microscopy.the histologic and ultrastructural findings in a fatal human case of marburg hemorrhagic fever are reported. marburg virus was isolated from fluids and tissues and was identified in tissues by immunohistochemistry and electron and immunoelectron microscopy. the distribution of viral antigen by light level immunohistochemistry correlated with histologic lesions and also with the ultrastructural localization of virions. the tissue distribution and lesions of marburg virus in this patient were cons ...19989491211
characterization of ebola virus entry by using pseudotyped viruses: identification of receptor-deficient cell lines.studies analyzing ebola virus replication have been severely hampered by the extreme pathogenicity of this virus. to permit analysis of the host range and function of the ebola virus glycoprotein (ebo-gp), we have developed a system for pseudotyping these glycoproteins into murine leukemia virus (mlv). this pseudotyped virus, mlv(ebola), can be readily concentrated to titers which exceed 5 x 10(6) infectious units/ml and is effectively neutralized by antibodies specific for ebo-gp. analysis of m ...19989525641
two strings to the bow of ebola virus. 19989546777
isolated case of ebola hemorrhagic fever with mucormycosis complications, kinshasa, democratic republic of the congo.a patient with undiagnosed ebola (ebo) hemorrhagic fever (ehf) was transferred from kikwit to a private clinic in kinshasa, democratic republic of the congo. a diagnosis of ehf was suspected on clinical grounds and was confirmed by detection of ebo virus-specific igm and igg in serum of the patient. during the course of the disease, although she had no known predisposing factors, the patient developed a periorbital mucormycosis abscess on eyelid tissue that was biopsied during surgical drainage; ...19999988159
treatment of ebola hemorrhagic fever with blood transfusions from convalescent patients. international scientific and technical committee.between 6 and 22 june 1995, 8 patients in kikwit, democratic republic of the congo, who met the case definition used in kikwit for ebola (ebo) hemorrhagic fever, were transfused with blood donated by 5 convalescent patients. the donated blood contained igg ebo antibodies but no ebo antigen. ebo antigens were detected in all the transfusion recipients just before transfusion. the 8 transfused patients had clinical symptoms similar to those of other ebo patients seen during the epidemic. all were ...19999988160
clinical, virologic, and immunologic follow-up of convalescent ebola hemorrhagic fever patients and their household contacts, kikwit, democratic republic of the congo. commission de lutte contre les epidémies à kikwit.a cohort of convalescent ebola hemorrhagic fever (ehf) patients and their household contacts (hhcs) were studied prospectively to determine if convalescent body fluids contain ebola virus and if secondary transmission occurs during convalescence. twenty-nine ehf convalescents and 152 hhcs were monitored for up to 21 months. blood specimens were obtained and symptom information was collected from convalescents and their hhcs; other body fluid specimens were also obtained from convalescents. arthr ...19999988162
a novel immunohistochemical assay for the detection of ebola virus in skin: implications for diagnosis, spread, and surveillance of ebola hemorrhagic fever. commission de lutte contre les epidémies à kikwit.laboratory diagnosis of ebola hemorrhagic fever (ehf) is currently performed by virus isolation and serology and can be done only in a few high-containment laboratories worldwide. in 1995, during the ehf outbreak in the democratic republic of congo, the possibility of using immunohistochemistry (ihc) testing of formalin-fixed postmortem skin specimens was investigated as an alternative diagnostic method for ehf. fourteen of 19 cases of suspected ehf met the surveillance definition for ehf and we ...19999988163
human infection due to ebola virus, subtype côte d'ivoire: clinical and biologic november 1994 after 15 years of epidemiologic silence, ebola virus reemerged in africa and, for the first time, in west africa. in côte d'ivoire, a 34-year-old female ethologist was infected while conducting a necropsy on a wild chimpanzee. eight days later, the patient developed a syndrome that did not respond to antimalarial drugs and was characterized by high fever, headache, chills, myalgia, and cough. the patient had abdominal pain, diarrhea, vomiting, and a macular rash, and was repatri ...19999988164
histopathological and immunohistochemical studies of lesions associated with ebola virus in a naturally infected chimpanzee.lesions caused by the côte d'ivoire subtype of ebola virus in a naturally infected young chimpanzee were characterized by histopathological and immunohistochemical methods. the predominant lesions consisted of multifocal necrosis in the liver and diffuse fibrinoid necrosis in the red pulp of the spleen. in these sites, macrophages contained large eosinophilic intracytoplasmic inclusion bodies. immunohistochemical staining indicated that macrophages were a major site of viral replication. the abs ...19999988165
ebola between outbreaks: intensified ebola hemorrhagic fever surveillance in the democratic republic of the congo, 1981-1985.surveillance for ebola hemorrhagic fever was conducted in the democratic republic of the congo from 1981 to 1985 to estimate the incidence of human infection. persons who met the criteria of one of three different case definitions were clinically evaluated, and blood was obtained for antibody confirmation by ifa. contacts of each case and 4 age- and sex-matched controls were also clinically examined and tested for immunofluorescent antibody. twenty-one cases of ebola infection (persons with an a ...19999988166
ebola hemorrhagic fever outbreaks in gabon, 1994-1997: epidemiologic and health control issues.from the end of 1994 to the beginning of 1995, 49 patients with hemorrhagic symptoms were hospitalized in the makokou general hospital in northeastern gabon. yellow fever (yf) virus was first diagnosed in serum by use of polymerase chain reaction followed by blotting, and a vaccination campaign was immediately instituted. the epidemic, known as the fall 1994 epidemic, ended 6 weeks later. however, some aspects of this epidemic were atypical of yf infection, so a retrospective check for other eti ...19999988167
the central structural feature of the membrane fusion protein subunit from the ebola virus glycoprotein is a long triple-stranded coiled coil.the ectodomain of the ebola virus gp2 glycoprotein was solubilized with a trimeric, isoleucine zipper derived from gcn4 (piigcn4) in place of the hydrophobic fusion peptide at the n terminus. this chimeric molecule forms a trimeric, highly alpha-helical, and very thermostable molecule, as determined by chemical crosslinking and circular dichroism. electron microscopy indicates that gp2 folds into a rod-like structure like influenza ha2 and hiv-1 gp41, providing further evidence that viral fusion ...19989600912
ebola goes pop: the filovirus from literature into film. 19989604849
[microscopic study of species specific features of hemostatic impairment in ebola virus infected monkeys].pathological changes were studied in the blood vessels of baboons, green, rhesus, and cynomolgus monkeys at the end-stage ebola (zaire) infection. marked microvascular lesions (capillary stasis, blood engorgement, thrombosis with blood cells, neutrophil accumulation, endothelial edema) were found in all the monkeys. these changes clearly indicate impaired organ blood supply. multiple hemorrhages were formed by diapedesis without vascular wall destruction. fibrin deposition and thrombi were featu ...19989608279
release of viral glycoproteins during ebola virus infection.maturation and release of the ebola virus glycoprotein gp were studied in cells infected with either ebola or recombinant vaccinia viruses. significant amounts of gp were found in the culture medium in nonvirion forms. the major form represented the large subunit gp1 that was shed after release of its disulfide linkage to the smaller transmembrane subunit gp2. the minor form were intact gp1,2 complexes incorporated into virosomes. vector-expressed gp formed spikes morphologically indistinguishab ...19989614872
ecology of marburg and ebola viruses: speculations and directions for future research.marburg and virulent ebola viruses are maintained in hosts that are rare and have little contact with humans or do not readily transmit virus. bats (particularly solitary microchiropteran species) are leading contenders as reservoir hosts. virus transfer to humans occurs by contact with the primary reservoir or via an intermediate animal that acquired infection from the reservoir and is, in turn, hunted by humans. an interesting possibility is that filoviruses may be arthropod or plant viruses, ...19999988176
a search for ebola virus in animals in the democratic republic of the congo and cameroon: ecologic, virologic, and serologic surveys, 1979-1980. ebola virus study teams.more than 30 years after the first outbreak of marburg virus disease in germany and yugoslavia and 20 years after ebola hemorrhagic fever first occurred in central africa, the natural history of filoviruses remains unknown. in 1979 and 1980, animals in the democratic republic of the congo and cameroon were collected during the dry season near the site of the 1976 ebola hemorrhagic fever epidemic. the study objectives were to identify local animals and search for evidence of ebola virus in their ...19999988177
[developing methods of specific heterologic immunoglobulins preparation for urgent prevention of ebola fever and study of their properties].methods for preventing and treating ebola virus hemorrhagic fever are not still available despite the fact that this virus have been studied for 20 years. methods of immunization of the animals (sheep, goats) non-susceptible to ebola virus with live virus preparations were developed to obtain the hyperimmune anti-ebola virus sera required to have highly immune antivirus gamma-globulins. these methods made it possible to obtain the immune sera having high virus-neutralizing antibodies. caprine im ...19989633237
dna vaccines expressing either the gp or np genes of ebola virus protect mice from lethal challenge.dna vaccines expressing the envelope glycoprotein (gp) or nucleocapsid protein (np) genes of ebola virus were evaluated in adult, immunocompetent mice. the vaccines were delivered into the skin by particle bombardment of dna-coated gold beads with the powderject-xr gene gun. both vaccines elicited antibody responses as measured by elisa and elicited cytotoxic t cell responses as measured by chromium release assays. from one to four vaccinations with 0.5 microgram of the gp dna vaccine resulted i ...19989657001
biochemical analysis of the secreted and virion glycoproteins of ebola virus.the glycoproteins expressed by a zaire species of ebola virus were analyzed for cleavage, oligomerization, and other structural properties to better define their functions. the 50- to 70-kda secreted and 150-kda virion/structural glycoproteins (sgp and gp, respectively), which share the 295 n-terminal residues, are cleaved near the n terminus by signalase. a second cleavage event, occurring in gp at a multibasic site (rrtrr downward arrow) that is likely mediated by furin, results in two glycopr ...19989658086
ebola haemorrhagic fever. 19989692135
marburg and ebola hemorrhagic fevers: does the primary course of infection depend on the accessibility of organ-specific macrophages? 19989709901
elisa for the detection of antibodies to ebola viruses.eias for igg and igm antibodies directed against ebola (ebo) viral antigens have been developed and evaluated using sera of animals and humans surviving infection with ebo viruses. the igm capture assay detected anti-ebo (subtype reston) antibodies in the sera of 5 of 5 experimentally infected animals at the time they succumbed to lethal infections. igm antibodies were also detected in the serum of a human who was infected with ebo (subtype reston) during a postmortem examination of an infected ...19999988184
pathogenesis of ebola virus infection: recent insights. 19989717212
[viral hemorrhagic fever--ebola hemorrhagic fever, marburg disease and lassa fever].viral hemorrhagic fevers include ebola hemorrhagic fever, marburg disease and lassa fever. the etiologic agents of the diseases, ebola virus, marburg virus and lassa virus, respectively, are categorized as viruses with biosafety level 4, because of their high mortality, high transmissibility and the lack of effective vaccines and therapeutic measures. ebola and marburg viruses are members of the filoviridae family and easily distinguishable from viruses of other families by the characteristic mo ...19989721531
[care of a patient with a rare and highly contagious virus disease. an emergency situation resulted in good preparedness].ever since the eradication of smallpox, sweden has been poorly furnished with emergency facilities for the care of patients with serious, very infectious diseases. national interest in creating such facilities was aroused by epidemics of haemorrhagic disease (first and foremost due to ebola virus during the present decade), at the same time as the first scandinavian case of haemorrhagic fever associated with a risk of person-to-person infection occurred in linköping. a special laboratory which h ...19979411086
haemorrhagic fevers and ecological perturbations.hemorrhagic fever is a clinical and imprecise definition for several different diseases. their main common point is to be zoonoses. these diseases are due to several viruses which belong to different families. the flaviviridae have been known for the longest time. they include the amaril virus that causes yellow fever and is transported by mosquitoes. viruses that have come to light more recently belong to three other families: arenaviridae, bunyaviridae, and filoviridae. they are transmitted by ...19979413538
the nonstructural small glycoprotein sgp of ebola virus is secreted as an antiparallel-orientated homodimer.the nonstructural small glycoprotein sgp, which unlike the transmembrane gp is synthesized from primary nonedited mrna species, is secreted from infected cells as a disulfide-linked homodimer. site-directed mutagenesis of all cysteine residues revealed that dimerization is due to an intermolecular disulfide linkage between cysteine residues at positions 53 and 306. formic acid hydrolysis of sgp demonstrated that sgp dimers consist of monomers in antiparallel orientation. another editing product ...19989792851
recombinant ebola virus nucleoprotein and glycoprotein (gabon 94 strain) provide new tools for the detection of human infections.after cloning and sequencing the glycoprotein (gp) gene of one of the gabonese strains of ebola virus isolated during the 1994-1996 outbreak, it was shown that the circulating virus was of the zaire subtype. this was confirmed in this study by cloning and sequencing the nucleoprotein (np) gene of this strain. these two structural proteins were also expressed as recombinant proteins and used in elisa tests. np was expressed as a his-tagged fusion protein in escherichia coli and was purified on re ...19989820131
crystal structure of the ebola virus membrane fusion subunit, gp2, from the envelope glycoprotein ectodomain.we have determined the structure of gp2 from the ebola virus membrane fusion glycoprotein by x-ray crystallography. the molecule contains a central triple-stranded coiled coil followed by a disulfide-bonded loop homologous to an immunosuppressive sequence in retroviral glycoproteins, which reverses the chain direction and connects to an alpha helix packed antiparallel to the core helices. the structure suggests that fusion peptides near the n termini form disulfide-bonded loops at one end of the ...19989844633
tropical myeloneuropathies interesting neurological syndrome, characterized by recurrent optic neuritis, cervical myelopathy from syringomyelia, paraparesis, amenorrhea-galactorrhea, and other endocrine problems, has been described among young black women in the french west indies. the etiology remains unknown, but possible links with devic's disease, acute disseminated encephalomyelitis, and neurotoxicity from quinolines in annona muricata teas have been postulated. the largest epidemic of neuropathy in this century o ...19989848004
long-term disease surveillance in bandundu region, democratic republic of the congo: a model for early detection and prevention of ebola hemorrhagic fever.after the large-scale outbreak of ebola hemorrhagic fever (ehf) in bandundu region, democratic republic of the congo, a program was developed to help detect and prevent future outbreaks of ehf in the region. the long-term surveillance and prevention strategy is based on early recognition by physicians, immediate initiation of enhanced barrier-nursing practices, and the use of an immunohistochemical diagnostic test performed on formalin-fixed skin specimens of patients who die of suspected viral ...19999988195
ebola virus inhibits induction of genes by double-stranded rna in endothelial cells.fatal cases of filoviral infection are accompanied by a marked immunosuppression. endothelial cells play a vital role in the host immune response through the expression of several immunomodulatory genes in addition to the expression of the antiviral genes, 2',5'-oligoadenylate synthetase [2'-5'(a)n], and the double-stranded rna (dsrna)-activated protein kinase (pkr). dsrna, an intermediate generated during viral replication and gene transcription of many viruses, leads to the induction of immuno ...19989875327
ebola virus outbreaks in the ivory coast and liberia, 1994-1995. 19999893379
comparison of the transcription and replication strategies of marburg virus and ebola virus by using artificial replication systems.the members of the family filoviridae, marburg virus (mbgv) and ebola virus (ebov), are very similar in terms of morphology, genome organization, and protein composition. to compare the replication and transcription strategies of both viruses, an artificial replication system based on the vaccinia virus t7 expression system was established for ebov. specific transcription and replication of an artificial monocistronic minireplicon was demonstrated by reporter gene expression and detection of the ...19999971816
an introduction to ebola: the virus and the disease. 19999988154
serologic survey among hospital and health center workers during the ebola hemorrhagic fever outbreak in kikwit, democratic republic of the congo, 1995.from may to july 1995, a serologic and interview survey was conducted to describe ebola hemorrhagic fever (ehf) among personnel working in 5 hospitals and 26 health care centers in and around kikwit, democratic republic of the congo. job-specific attack rates estimated for kikwit general hospital, the epicenter of the ehf epidemic, were 31% for physicians, 11% for technicians/room attendants, 10% for nurses, and 4% for other workers. among 402 workers who did not meet the ehf case definition, 12 ...19999988171
[ebola hemorrhagic fever and marburg virus disease: their virological and clinical aspects]. 199910088344
[effects of repeated administration of ebola virus preparations on dynamics of immunologic parameters]. 199910190013
prevalence of igg antibodies to ebola virus in individuals during an ebola outbreak, democratic republic of the congo, 1995.during the 1995 outbreak of ebola (ebo) hemorrhagic fever in kikwit, democratic republic of congo, two surveys using a new elisa for ebo (subtype zaire) virus antigen were conducted to assess the prevalence of ebo igg antibodies among residents of kikwit and the surrounding area. the first study determined the proportion of antibody-positive individuals who were self-identified forest and city workers from the kikwit area. serum samples from 9 (2.2%) of 414 workers had igg ebo antibodies. the se ...19999988172
ebola (subtype reston) virus among quarantined nonhuman primates recently imported from the philippines to the united april 1996, laboratory testing of imported nonhuman primates (as mandated by quarantine regulations) identified 2 cynomolgus macaques (macaca fascicularis) infected with ebola (subtype reston) virus in a us-registered quarantine facility. the animals were part of a shipment of 100 nonhuman primates recently imported from the philippines. two additional infected animals, who were thought to be in the incubation phase, were identified among the remaining 48 animals in the affected quarantine ro ...19999988173
epidemiology of ebola (subtype reston) virus in the philippines, 1996.ebola (subtype reston [ebo-r]) virus infection was detected in macaques imported into the united states from the philippines in march 1996. studies were initiated in the philippines to identify the source of the virus among monkey-breeding and export facilities, to establish surveillance and testing, and to assess the risk and significance of ebo-r infections in humans who work in these facilities. over a 5-month period, acutely infected animals were found at only one facility, as determined usi ...19999988174
field investigations of an outbreak of ebola hemorrhagic fever, kikwit, democratic republic of the congo, 1995: arthropod studies.during the final weeks of a 6-month epidemic of ebola hemorrhagic fever in kikwit, democratic republic of the congo, an extensive collection of arthropods was made in an attempt to learn more of the natural history of the disease. a reconstruction of the activities of the likely primary case, a 42-year-old man who lived in the city, indicated that he probably acquired his infection in a partly forested area 15 km from his home. collections were made throughout this area, along the route he follo ...19999988178
search for the ebola virus reservoir in kikwit, democratic republic of the congo: reflections on a vertebrate collection.a 3-month ecologic investigation was done to identify the reservoir of ebola virus following the 1995 outbreak in kikwit, democratic republic of the congo. efforts focused on the fields where the putative primary case had worked but included other habitats near kikwit. samples were collected from 3066 vertebrates and tested for the presence of antibodies to ebola (subtype zaire) virus: all tests were negative, and attempts to isolate ebola virus were unsuccessful. the investigation was hampered ...19999988179
detection and molecular characterization of ebola viruses causing disease in human and nonhuman primates.ebola (ebo) viruses were detected in specimens obtained during the hemorrhagic fever outbreak among humans in kikwit, democratic republic of the congo (drc), in 1995 (subtype zaire) and during an outbreak of disease in cynomolgus macaques in alice, texas, and the philippines in 1996 (subtype reston). reverse transcriptase-polymerase chain reaction assays were developed and proven effective for detecting viral rna in body fluids and tissues of infected individuals. little change was seen in the n ...19999988180
persistence and genetic stability of ebola virus during the outbreak in kikwit, democratic republic of the congo, 1995.ebola virus persistence was examined in body fluids from 12 convalescent patients by virus isolation and reverse transcription-polymerase chain reaction (rt-pcr) during the 1995 ebola hemorrhagic fever outbreak in kikwit, democratic republic of the congo. virus rna could be detected for up to 33 days in vaginal, rectal, and conjunctival swabs of 1 patient and up to 101 days in the seminal fluid of 4 patients. infectious virus was detected in 1 seminal fluid sample obtained 82 days after disease ...19999988181
clinical virology of ebola hemorrhagic fever (ehf): virus, virus antigen, and igg and igm antibody findings among ehf patients in kikwit, democratic republic of the congo, 1995.ebola hemorrhagic fever (ehf) patients treated at kikwit general hospital during the 1995 outbreak were tested for viral antigen, igg and igm antibody, and infectious virus. viral antigen could be detected in virtually all patients during the acute phase of illness, while antibody was not always detectable before death. virus was also isolated from patients during the course of their febrile illness, but attempts to quantify virus in vero e6 cells by standard plaque assay were often unsuccessful ...19999988182
an analysis of features of pathogenesis in two animal models of ebola virus infection.virus reproduction and the time course of changes in liver and kidney functions and in the blood clotting system were studied in the visceral organs of green monkeys and baboons infected with ebola virus (subtype zaire). it was shown that monocytes and macrophages were the first cells to be infected with the virus, followed by hepatocytes, adrenocorticocytes, fibroblasts, and endotheliocytes. the early and late pathologic changes in the monkey organs are described. biochemical data on changes in ...19999988185
pathogenesis of experimental ebola virus infection in guinea pigs.the subtype zaire of ebola (ebo) virus (mayinga strain) was adapted to produce lethal infections in guinea pigs. in many ways, the disease was similar to ebo infections in nonhuman primates and humans. the guinea pig model was used to investigate the pathologic events in ebo infection that lead to death. analytical methods included immunohistochemistry, in situ hybridization, and electron microscopy. cells of the mononuclear phagocyte system, primarily macrophages, were identified as the early a ...19999988186
preparation and use of hyperimmune serum for prophylaxis and therapy of ebola virus obtain hyperimmune serum appropriate for the treatment of filovirus infection, methods were developed to immunize nonsusceptible animals with live ebola (ebo) virus preparations. immune plasma with high elisa and neutralization-specific antibody titers was obtained by multiple immunization of sheep and goats with preparations of live ebo virus. goat immunoglobulin was prepared by cohn's method and tested on guinea pigs, using an ebo virus strain that is highly pathogenic for guinea pigs. prop ...19999988187
a mouse model for evaluation of prophylaxis and therapy of ebola hemorrhagic fever.the zaire subtype of ebola virus (ebo-z) is lethal for newborn mice, but adult mice are resistant to the virus, which prevents their use as an animal model of lethal ebola infection. we serially passed ebo-z virus in progressively older suckling mice, eventually obtaining a plaque-purified virus that was lethal for mature, immunocompetent balb/c and c57bl/6 inbred and icr (cd-1) outbred mice. pathologic changes in the liver and spleen of infected mice resembled those in ebo-z-infected primates. ...19989728532
[ebola virus: what the practitioner needs to know].the ebola virus is an rna virus of filoviridae family. the earliest documented fatal epidemic of ebola hemorrhagic occurred in 1976. there are four genetically different subtypes of ebola virus. the virus remains in the blood for several weeks, can maintain its infectivity for several weeks at 20 degrees c outside the body, and survives for several weeks in corpses. isolation of ebola virus requires level 4 laboratory security conditions. specimens are obtained by culturing mammal cells. identif ...19989791600
[dynamics of immunologic indicators in guinea pigs upon administering various preparations of the ebola virus].immunological and hematological values are analyzed in guinea pigs infected with ebola virus (ev) strain weakly pathogenic for these animals, inactivated ev, and ev strain adapted to guinea pigs and causing a lethal infection in them. the disease induced by lethal ev differed from that induced by other ev strains. blastic wave in lymphoid organs in the absence of antibodies to ev detected by enzyme immunoassay, elimination of circulating immune complexes, and appearance of eosinophils in the blo ...19989791881
antiviral drug therapy of filovirus infections: s-adenosylhomocysteine hydrolase inhibitors inhibit ebola virus in vitro and in a lethal mouse model.ebola (subtype zaire) viral replication was inhibited in vitro by a series of nine nucleoside analogue inhibitors of s-adenosylhomocysteine hydrolase, an important target for antiviral drug development. adult balb/c mice lethally infected with mouse-adapted ebola virus die 5-7 days after infection. treatment initiated on day 0 or 1 resulted in dose-dependent protection, with mortality completely prevented at doses > or =0.7 mg/kg every 8 h. there was significant protection (90%) when treatment w ...19999988190
a mouse model for evaluation of prophylaxis and therapy of ebola hemorrhagic fever.the zaire subtype of ebola virus (ebo-z) is lethal for newborn mice, but adult mice are resistant to the virus, which prevents their use as an animal model of lethal ebola infection. we serially passed ebo-z virus in progressively older suckling mice, eventually obtaining a plaque-purified virus that was lethal for mature, immunocompetent balb/c and c57bl/6 inbred and icr (cd-1) outbred mice. pathologic changes in the liver and spleen of infected mice resembled those in ebo-z-infected primates. ...19999988191
ebola outbreak in kikwit, democratic republic of the congo: discovery and control measures.the ebola epidemic in kikwit, democratic republic of the congo, was recognized because of a nosocomial outbreak in kikwit general hospital. initially, a diagnosis of shigella infection was suspected because many patients presented with bloody diarrhea. on 4 may 1995, blood samples from 14 acutely ill patients were sent to the centers for disease control and prevention (atlanta), and on 9 may, a diagnosis of ebola hemorrhagic fever was confirmed. the major disease control measures that were under ...19999988192
us policy for disease control among imported nonhuman 1990, in response to the occurrence of ebola virus (subsequently identified as subtype reston) infection among cynomolgus monkeys imported from the philippines, the united states implemented strict disease control measures for handling nonhuman primates during transit and quarantine and initiated importer facility compliance inspections. disease control measures emphasized protection of workers from exposure, use of containment facilities and procedures, measures to prevent spread of infectio ...19999988196
characteristics of filoviridae: marburg and ebola viruses.filoviruses are enveloped, nonsegmented negative-stranded rna viruses. the two species, marburg and ebola virus, are serologically, biochemically, and genetically distinct. marburg virus was first isolated during an outbreak in europe in 1967, and ebola virus emerged in 1976 as the causative agent of two simultaneous outbreaks in southern sudan and northern zaire. although the main route of infection is known to be person-to-person transmission by intimate contact, the natural reservoir for filo ...199910024977
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