pathogenic potential of filoviruses: role of geographic origin of primate host and virus strain.african filoviruses have caused outbreaks of fulminating hemorrhagic fever among humans. in 1989, related filoviruses were isolated from cynomolgus monkeys imported into the united states from the philippines. the pathogenic potential of these new filoviruses was compared in 16 asian monkeys (macaca fascicularis-cynomolgus) and 16 african monkeys (cercopithecus aethiops-african green) using african filoviruses from zaire (ebola virus) and sudan or asian filoviruses (reston and pennsylvania). afr ...19921527410
surveillance and control of emerging zoonoses."emerging zoonoses" are defined as zoonotic diseases caused either by apparently new agents, or by previously known microorganisms, appearing in places or in species in which the disease was previously unknown. new animal diseases with an unknown host spectrum are also included in this definition. natural animal reservoirs represent a more frequent source of new agents of human disease than the sudden appearance of a completely new agent. factors explaining the emergence of a zoonotic or potenti ...19921462655
filovirus clearance in non-human primates.there has been concern in the usa and europe about filovirus outbreaks in recently imported monkeys, and possible transmission to human beings. healthy monkeys have been found to have low-titre immunofluorescence antibody (ifa) to asian filoviruses (reston and pennsylvania viruses) as well as to the african filoviruses that caused fulminating human outbreaks in the 1970s (ebola [zaire] and sudan viruses). we have assessed whether such monkeys are a risk to man. we studied 42 non-human primates; ...19921354784
combined simian hemorrhagic fever and ebola virus infection in cynomolgus monkeys.simian hemorrhagic fever (shf) virus and a new strain of ebola virus were isolated concurrently in recently imported cynomolgus monkeys (macaca fascicularis) being maintained in a quarantine facility. ebola virus had never been isolated in the u.s. previously and was presumed to be highly pathogenic for humans. a chronology of events including measures taken to address the public health concerns is presented. the clinicopathologic features of the disease were abrupt anorexia, splenomegaly, marke ...19921318446
outbreak of fatal illness among captive macaques in the philippines caused by an ebola-related filovirus.following the detection of an ebola-like virus in cynomolgus macaques recently imported into the united states from the philippines, studies were initiated to document transmission at export facilities located in the latter country. at one export facility, 52.8% of 161 monkeys that died over a 2.5-month period were shown to be infected with this virus using an enzyme-linked immunosorbent assay to detect antigen in liver homogenates. a case fatality rate of 82.4% was documented for the infected m ...19921621890
[ebola virus reproduction in cell cultures].ebola-zaire virus production in vero and bgm cells was studied. the cpe developed in both cell cultures. the cell monolayer destruction by 80-90% was seen at a low multiplicity of infection in 7-8 days after virus inoculation. an overlay composition was developed for virus titration using plaque assay. the plaque production was shown to be directly proportional to the virus dose. the curve of ebola virus production in vero cell culture fluid was determined. at a multiplicity of infection of 0.01 ...19921279896
a case of ebola virus november 1976 an investigator at the microbiological research establishment accidentally inoculated himself while processing material from patients in africa who had been suffering from a haemorrhagic fever of unknown cause. he developed an illness closely resembling marburg disease, and a virus was isolated from his blood that resembled marburg virus but was distinct serologically. the course of the illness was mild and may have been modified by treatment with human interferon and convalesce ...1977890413
ultrastructure of ebola virus particles in human liver.electron microscopy of tissues from two necropsies carried out in the sudan on patients with ebola virus infection identified virus particles in lung and spleen, but the main concentrations of ebola particles were seen in liver sections. viral precursor proteins and cores were found in functional liver cells, often aligned in membrane-bound aggregations. complete virions, usually found only extracellularly, were mainly seen as long tubular forms, some without cores. many tubular forms had 'enlar ...1978641193
ebola virus virulence for newborn mice. 1979536744
the envelope glycoprotein of ebola virus contains an immunosuppressive-like domain similar to oncogenic retroviruses.genomic rna of a zaire strain of ebola virus was cloned, and cdna inserts specific for the glycoprotein gene were isolated and sequenced. the determined sequence has only one open reading frame encoding 318 amino acids and is part of orf-4 on the plus rna strand. the putative transcriptional stop site (3' aauucuuuuu 5') and the transcriptional start site (3' aacuacuucuaauu..5') were identified. computer-assisted comparison of the amino acid sequence of the c-terminal part of protein encoded by o ...19921299611
ebola haemorrhagic fever: experimental infection of monkeys.experimental infection of rhesus and vervet monkeys with ebola virus produced a uniformly fatal illness. the course of the disease resembled that found in man with weight loss, anorexia, fever, haemorrhages and skin rash being frequently seen. viraemia was obvious within two days of infection and persisted until death which occurred between days five and eight. virus was found in high concentrations in several organs but particularly in the liver, spleen, and lungs.1978418537
measurement of antibodies to ebola virus in human sera from n. w.-zaire. 1979395911
[lassa, marbourg and ebola viruses: new features of african tropical pathology. ii. epidemiology. public health problems (author's transl)].lassa, marbourg and ebola viruses are characterised by their endemo-epidemicity in tropical africa, by their potential of inter-human transmission, by their gravity (30 to 50% mortality in cases admitted to hospital) and by the difficulty of their aetiological diagnosis. this results in a public health problem for countries in non-endemic regions receiving travellers coming from africa. this problem is related to the risk of importation of cases, a risk which should not be exaggerated but nor sh ...1978364408
filovirus contamination of cell cultures.the filoviruses marburg and ebola comprise a newly recognized family of viruses. the first filovirus to be isolated was marburg virus in 1967. this virus was imported in shipments of african green monkeys from uganda and infected several cell-culture technicians, with serious illness resulting. the rarity of marburg and ebola virus transmission, decreasing use of imported african monkeys, and quarantine efforts have presumably been responsible for the lack of additional episodes until 1989, when ...19921478345
[african hemorrhagic fever caused by ebola virus]. 1979503930
[infections by marburg and ebola viruses: guide for their diagnosis, treatment and control]. 1978150845
ebola and marburg viruses: ii. thier development within vero cells and the extra-cellular formation of branched and torus forms.the development of marburg virus and the sudanese and zaire strains of ebola virus in vero cells as visualized by electron microscopy is described. despite differences in timing, all three strains appear to pass through identical stages of development. initially there is a large increase in nucleolus material, and viral precursor material arranges itself in spirals and then into tubes. the cells fill with core material, which passes to the plasmalemma, which often proliferates. each virion passe ...1979119829
ebola virus infection in imported primates--virginia, 1989. 19892511410
[ebola virus three years later (author's transl)].sporadic cases and data from serologic surveys give evidence that ebola virus is still active in northern zaïre after the first outbreak in 1976. it is also active in southern sudan where it is, from august 1979, responsible of a new epidemic focus. in addition, serological surveys demonstrate that its dispersion area comprises several other african countries. physicians practising in central africa must be aware of this fact. serological test is necessary to confirm the diagnosis. this confirma ...1979119124
[recent lassa, marbourg and ebola viruses in african tropical viruses. i. semiology--physiopathology--diagnosis--treatment (author's transl)].three new viruses have been identified in africa during the present decade. they may cause sporadic cases or limited outbreaks, and they are probably endemic in areas which are still ill-defined. severe forms of infection lead to the haemorrhagic syndrome or to hypovolemic shock, the physiopathology of which is being studied. the case-fatality ratio of severe cases is between 30 and 85 per cent. nosocomial outbreaks have been observed, but they can be avoided if appropriate barrier nursing measu ...1978569288
ebola virus: a comparison, at ultrastructural level, of the behaviour of the sudan and zaire strains in monkeys.histopathological and electron microscopical examination of human liver specimens collected during the ebola haemorrhagic fever outbreaks in zaire and sudan indicated that zairean strains of the virus produced more extensive lesions. experimental infection of rhesus monkeys wiht zairean and sudanese strains of ebola virus produced similar changes to those found in man. in zairean strain infections large numbers of virus particles were found in the liver, lung and spleen accompanied by extensive ...1978106868
arbovirus infections and viral haemorrhagic fevers in uganda: a serological survey in karamoja district, 1984.sera collected in may 1984 from 132 adult residents of karamoja district, uganda, were examined by haemagglutination inhibition tests for antibodies against selected arboviruses, namely chikungunya and semliki forest alphaviruses (togaviridae); dengue type 2, wesselsbron, west nile, yellow fever and zika flaviviruses (flaviviridae); bunyamwera, ilesha and tahyna bunyaviruses (bunyaviridae); and sicilian sandfly fever phlebovirus (bunyaviridae); and by immunofluorescence tests against certain hae ...19892559514
[marburg, lassa and ebola virus as cause of hemorrhagic fever]. 1978352653
ebola and marburg viruses: i. some ultrastructural differences between strains when grown in vero cells.a strain of marburg virus and two strains of ebola virus grown in vero cells were compared by electron microscopy. the outer coat of the marburg virion appeared to be more resistant to erosion by negative staining techniques than that of the epbola strains. marburg virus commonly produced "torus" forms and short filaments; the zaire strain of ebola produced extensive branched forms and very long filaments; the sudan strain of ebola produced shorter, less branched structures but very many aberran ...197994087
after marburg, ebola. 197765668
sequence analysis of the marburg virus nucleoprotein gene: comparison to ebola virus and other non-segmented negative-strand rna viruses.the first 3000 nucleotides from the 3' end of the marburg virus (mbg) genome were determined from cdna clones produced from genomic rna and mrna. identified in the sequence was a short putative leader sequence at the extreme 3' end, followed by the complete nucleoprotein (np) gene. the 5' end of the np mrna was determined as was the polyadenylation site for the np gene. the transcriptional start (3' uucuucuuauaauu..) and termination (3' ..uaauucuuuuu) signals of the mbg np gene are very similar ...19921538192
viral haemorrhagic fevers of man.this article reviews the current state of knowledge on the viral haemorrhagic fevers that infect man, namely smallpox, chikungunya fever, dengue fever, rift valley fever, yellow fever, crimean haemorrhagic fever, kyasanur forest disease, omsk haemorrhagic fever, argentinian haemorrhagic fever (junin virus), bolivian haemorrhagic fever (machupo virus), lassa fever, haemorrhagic fever with renal syndrome, and marburg and ebola virus diseases.1978310725
evidence for occurrence of filovirus antibodies in humans and imported monkeys: do subclinical filovirus infections occur worldwide?in the present serological study 120 monkey sera from different species originating from the philippines, china, uganda and undetermined sources and several groups of human sera comprising a total of 1288 specimens from people living in germany were examined for the presence of antibodies directed against filoviruses (marburg virus, strain musoke/ebola virus, subtype zaire, strain mayinga/reston virus). sera were screened using a filovirus-specific enzyme-linked immunosorbent assay (elisa). elis ...19921579085
association of ebola-related reston virus particles and antigen with tissue lesions of monkeys imported to the united states.during 1989-1990, an epizootic involving a filovirus closely related to ebola virus occurred in a reston, virginia, primate-holding facility. tissues were collected from cynomolgus monkeys and examined by electron microscopy and immunohistochemistry for ebola-related viral antigen. viral replication was extensive in fixed tissue macrophages, interstitial fibroblasts of many organs, circulating macrophages and monocytes, and was observed less frequently in vascular endothelial cells, hepatocytes, ...19921597531
update: nonhuman primate importation.beginning in november 1989, a number of cynomolgus monkeys (macaca fascicularis) imported into the united states were found to have been infected with a previously unrecognized ebola-like filovirus. this report summarizes findings of surveillance and serologic testing of nonhuman primates imported under special permits from june 1990 through september 1991.19911656185
seroepidemiological study of filovirus related to ebola in the philippines. 19911671441
viral hemorrhagic fever antibodies in nigerian populations.using the immunofluorescence test, a serosurvey for antibodies to five viral agents associated with hemorrhagic febrile infections was conducted with 1,677 human sera from different parts of nigeria. three hundred fifty-seven (21.3%) were positive for lassa virus antibody, while antibodies to rift valley fever virus were detected in 42 (2.5%) of the sera. testing for rift valley fever virus antibody was confirmed by plaque reduction neutralization test. antibodies to ebola and marburg viruses we ...19883128130
virus zoonoses and their potential for contamination of cell cultures.silent virus infections of laboratory animals present a human health hazard, from direct exposure and from contamination of biological products for human use. here we report two recent examples. in 1989, an outbreak of lymphocytic choriomeningitis virus (lcmv) infections was recognized among workers at a cancer research center after an animal caretaker developed viral meningitis. investigation revealed that multiple tumor cell lines at the facility were infected with lcmv, as were research anima ...19911794619
[clinico-epidemiologic and laboratory research on hemorrhagic fevers in guinea].in 1982-1983, were reported the cases of haemorrhagic fevers among populations living in the madina-ula district of guinea. clinico-epidemiological and serological studies (experimental studies) reveal into presumption of ebola and lassa fever viruses significance in the etiology of the disease outbreaks. antibodies to ebola virus were recognized in 19% from total number of sweating reconvalescent patients with the same clinical features, in order to 8% in healthy local populations. antibodies t ...19873440310
sequence of the major nucleocapsid protein gene of pneumonia virus of mice: sequence comparisons suggest structural homology between nucleocapsid proteins of pneumoviruses, paramyxoviruses, rhabdoviruses and filoviruses.the complete nucleotide sequence of gene 3 of pneumonia virus of mice has been determined, and the 5' end of the mrna mapped using a modification of the polymerase chain reaction technique. the gene contains a single open reading frame, beginning with a 5'-proximal aug initiation codon, encoding a polypeptide with a predicted mr of 43141. expression of the gene 3 protein in escherichia coli and in vitro showed that it reacted with virus-specific antiserum and comigrated with the major nucleocaps ...19911848602
preliminary report: isolation of ebola virus from monkeys imported to epizootic caused by an ebola-related filovirus and by simian haemorrhagic fever virus began among cynomolgus monkeys in a us quarantine facility after introduction of monkeys from the philippines. this incident, the first in which a filovirus has been isolated from non-human primates without deliberate infection, raises the possibility that cynomolgus monkeys could be a reservoir of ebola virus infection.19901968529
detection of ebola-like viruses by immunofluorescence. 19901979412
enzyme immunosorbent assay for ebola virus antigens in tissues of infected primates.a sandwich enzyme immunosorbent assay (eia) using a mixture of mouse monoclonal antibodies for antigen capture and polyclonal hyperimmune rabbit anti-ebola virus serum for antigen detection was developed and evaluated on the tissues of monkeys naturally or experimentally infected with strains of ebola viruses. when compared with virus isolation, the antigen detection eia was both sensitive and specific: 44 of 45 (97.7%) liver homogenates and 38 of 41 (92.7%) spleen homogenates that were culture ...19921572982
ebola virus and hemorrhagic fever: andromeda strain or localized pathogen? 1979111590
[the other types of viral hepatitis].hepatitis due to viruses other than a, b, c, d, e are numerous but uncommon in adults. among the group of herpesviridae (hsv, cmv, ebv, vzv), clinical hepatitis is usually suggestive of disseminated viral infection. fulminant hepatitis occasionally observed in immunocompromised hosts are due to hsv, and vzv, but exceptionally to ebv. many new techniques using specific monoclonal antibodies permit an accurate and fast diagnosis. three drugs (vidarabine, acyclovir, ribavirine) have been shown to b ...19902164704
the pathology of experimental ebola virus infection in monkeys.six rhesus and two vervet monkeys were infected intraperitoneally with ebola virus. they developed an acute haemorrhagic fever with skin rash 4 days later and died 6--12 days after infection. histopathological lesions of acute necrosis were present in the liver, spleen, lymph nodes, lungs and testes. the presence of fibrin thrombi in several organs was suggestive of the occurrence of disseminated intravascular coagulation during the infection.1978102747
primate viral diseases in perspective.the recent occurrence of fatal herpesvirus simiae (b virus) infection in human subjects has again focused the attention of primatologists on this virus. b virus, however, is only one of a number of viral diseases that plays a role in primate colony management. this report is to emphasize to the primatologist a number of viruses other than h. simiae, with high morbidity and mortality rates, of importance for health management of nonhuman primate animal colonies. this concept is supported by the r ...19902174083
use of immunoelectron microscopy to show ebola virus during the 1989 united states epizootic.a filovirus, serologically related to ebola virus, was detected by "post-embedment" immunoelectron microscopical examination of ma-104 cells. these had been infected by inoculation with serum samples obtained during the 1989 epizootic in cynomolgus monkeys (macaca fascicularis), imported from the philippines and maintained at reston, virginia, usa, a primate holding facility. the immunoelectron microscopy method, when used in conjunction with standard transmission electron microscopy (tem) of in ...19902229429
antibody prevalence against haemorrhagic fever viruses in randomized representative central african populations.between 1985 and 1987, 5,070 randomly selected persons living in 6 central african countries (cameroon, central african republic, chad, congo, equatorial guinea and gabon) were checked for serological evidence of haemorrhagic fever. rural and urban areas were studied, including ecoclimatic zones ranging from dry savana to tropical rain forest. virus-reactive antibodies were found with all antigens tested, and the global prevalence of positive sera was distributed as follows: crimean-congo haemor ...19892505350
update: ebola-related filovirus infection in nonhuman primates and interim guidelines for handling nonhuman primates during transit and quarantine. 19902104655
antibodies to haemorrhagic fever viruses in madagascar populations.sera of 381 adult people from 5 areas in madagascar were tested by the indirect immunofluorescence method for antibodies against congo-crimean haemorrhagic fever and rift valley fever viruses (bunyaviridae), ebola (strains zaire and sudan) and marburg viruses (filoviridae), and lassa virus (arenaviridae). the highest prevalence rate was that of ebola virus (4.5%). as no haemorrhagic syndrome has been found associated with this virus, the possible presence of a less pathogenic, antigenically rela ...19892515626
epidemiology of hemorrhagic fever viruses.twelve distinct viruses associated with hemorrhagic fever in humans are classified among four families: arenaviridae, which includes lassa, junin, and machupo viruses; bunyaviridae, which includes rift valley fever, crimean-congo hemorrhagic fever, and hantaan viruses; filoviridae, which includes marburg and ebola viruses; and flaviviridae, which includes yellow fever, dengue, kyasanur forest disease, and omsk viruses. most hemorrhagic fever viruses are zoonoses, with the possible exception of t ...19892546247
prospects for treatment of viral hemorrhagic fevers with ribavirin, a broad-spectrum antiviral drug.ribavirin, a broad-spectrum antiviral drug, is active against hemorrhagic fever viruses (with the exception of ebola virus) in cell culture systems. in model infections with arenaviruses in guinea pigs and monkeys, ribavirin has demonstrated both prophylactic and therapeutic efficacy. in therapeutic studies it has not prevented late-onset neurologic disease. in human cases of lassa fever, it significantly reduces mortality when administered before day 7 of illness to persons at high risk. in rod ...19892546248
nosocomial viral infections: iii. guidelines for prevention and control of exanthematous viruses, gastroenteritis viruses, picornaviruses, and uncommonly seen viruses.this communication is the third in a four-part series on nosocomial viral infections from the strong memorial hospital. this third article discusses guidelines for prevention and control of exanthematous viruses, gastroenteritis, viruses, adenoviruses and the picornaviruses other than rhinoviruses. several uncommonly seen viruses, such as the virus of creutzfeldt-jakob disease and marburg, ebola, and lassa fever viruses, also are reviewed briefly.19816260699
rapid identification of ebola virus and related filoviruses in fluid specimens using indirect immunoelectron microscopy.recent filoviral outbreaks in animal primates have raised public awareness of the potential for filoviruses to become a public health concern; methods that efficiently identify these viruses are therefore of high priority. an indirect immunoelectron microscopy method, which uses homologous guinea pig polyclonal antiserum, successfully identified ebola-related (reston) virus particles in serum and tissue culture fluid specimens with infectivity titres of 300 plaque forming units (pfu) per ml or m ...19912066435
detection of viral antigens in formalin-fixed specimens by enzyme treatment.enzyme treatment (protease or trypsin) was applied to formalin-fixed paraffin-embedded materials and virus-infected cultured cells to detect viral antigens by immunofluorescence. the viral antigens were demonstrated in several organs of autopsy or biopsy cases of which diagnoses had been established by immunofluorescence or virus isolation using frozen materials, or suspected on the basis of serology and/or histopathological findings. these included herpes simplex, varicella-zoster, cytomegalo, ...19836326644
development of an immunofluorescence focus assay for ebola virus.a 48-h indirect immunofluorescence focus assay for the quantitation of ebola virus was developed, utilizing hela-229 cell monolayers. the dose dependency and the sensitivity of this assay as compared with conventional assays are reported. this indirect immunofluorescence focus assay can be used as a rapid, quantitative test for the detection of ebola virus, an agent from africa known to cause hemorrhagic fever.19836352735
ebola virus. 19902167118
haematological and biochemical monitoring of ebola infection in rhesus monkeys: implications for patient management.patients with severe viral infections such as lassa or ebola may be denied adequate laboratory investigations because of justifiable fears among laboratory staff. this study in monkeys was designed to provide comprehensive haematological and biochemical monitoring in a contained environment during all stages of ebola infection. marked neutrophilia, depletion of lymphocytes, and early failure of platelet aggregation preceded a consumption coagulopathy with a microangiopathic haemolytic anaemia, t ...19836138602
identification and analysis of ebola virus messenger rna.six messenger rna species of ebola virus were identified in infected vero e6 cells. virion rna hybridizes to each of the mrnas, confirming that ebola virus possesses a negative-stranded rna genome. the mrnas are monocristronic transcripts, are synthesized in the presence of actinomycin d, and are polyadenylated. in vitro translation of mrna preparations results in the synthesis of five authentic viral proteins and a putative unglycosylated form of the glycoprotein, demonstrated by immunoprecipit ...19872881398
[diagnosis of fever in a patient returning from black africa (author's transl)].the diagnostic problems which arise when fever occurs in a patient returning from black africa are more and more frequently encountered because of the multiplication of rapid connections with this continent. analysis of the main etiologies leads the author to review most of the specifically tropical diseases. however, cosmopolitan diseases should not be underrated. the author emphasizes the high incidence of pernicious malaria, liver amebiasis, and typho-paratyphoid fevers, along with the necess ...19826280318
seasonal variation in antibodies against ebola virus in kenyan fever patients. 19862871413
viral diseases involving the liver.even though hav, hbv and hnanb viruses are responsible for most of the viral hepatitis cases, many other viruses have been reported to cause hepatic injury. these viruses may involve the liver, either as part of a systemic illness (e.g. ebv, cmv, hsv) or as the primary target organ (e.g. yellow fever virus, lassa fever virus, ebola virus). clinically overt hepatocellular dysfunction is rare in such viral infections. biochemical disturbance of hepatic functions shown, for example, by rises in ast ...19872822180
a study of viral and rickettsial exposure and causes of fever in juba, southern sudan.patients presenting at the juba teaching hospital, either with fever of undetermined origin or with a clinical cause of fever, gave evidence of exposure to a wide range of viral and rickettsial agents. serological tests showed high antibody levels to flaviviruses (56.9%) and alphaviruses (29.2%), with lesser levels of bunyamweraviruses (3.8%), rift valley fever (2.3%), and sandfly fever (0.75%). flavivirus exposure was significantly associated with clinical evidence of liver disease; repeated ex ...19882855284
the nucleoprotein gene of ebola virus: cloning, sequencing, and in vitro expression.genomic and messenger rnas of a zaire strain of ebola virus were cloned, and inserts specific for the nucleoprotein gene were isolated and sequenced. the nucleoprotein gene is located proximal to the 3' end of the genome and is preceeded by a putative leader sequence. the gene begins with the transcriptional start site sequence 3'-uacuccuucuaauu..., and ends with the polyadenylation site sequence 3'-... uaauucuuuuuu. the predicted coding region is 2217 bases in length and encodes a protein that ...19892718390
physicochemical inactivation of lassa, ebola, and marburg viruses and effect on clinical laboratory analyses.clinical specimens from patients infected with lassa, ebola, or marburg virus may present a serious biohazard to laboratory workers. we have examined the effects of heat, alteration of ph, and gamma radiation on these viruses in human blood and on the electrolytes, enzymes, and coagulation factors measured in laboratory tests that are important in the care of an infected patient. heating serum at 60 degrees c for 1 h reduced high titers of these viruses to noninfectious levels without altering t ...19846490832
ebola virus infection in imported primates--united late november 1989, ebola virus was isolated from cynomolgus monkeys (macaca fascicularis) imported into the united states from the philippines via amsterdam and new york. during quarantine in a primate facility in virginia, numerous macaques died, some with findings consistent with simian hemorrhagic fever (shf). the us army medical research institute of infectious diseases tested 10 animals and, from 3, isolated shf from tissues and serum; however, 5 other animals of the 10 tested were posi ...19902302743
firsthand clinical observations of hemorrhagic manifestations in ebola hemorrhagic fever in zaire.about 5 weeks after the beginning of the outbreak of ebola virus fever in yambuku, zaire, several acute cases of the disease were observed. all of those affected had the following common signs and symptoms: sudden onset of high fever, with chills, headache, myalgia, anorexia, nausea, abdominal pain, sore throat, expressionless face, and profound prostration. in some cases, on around the fifth day of the acute phase, the appearance of an exanthematous rash on the trunk announced the hemorrhagic m ...19892749110
antibodies against haemorrhagic fever viruses in kenya populations.human sera from lodwar (77 sera), nzoia (841 sera), masinga (251 sera), laisamis (174 sera) and the malindi/kilifi area (556 sera) in kenya were tested by indirect immunofluorescence for antibodies against marburg, ebola (zaire and sudan strains), congo haemorrhagic fever, rift valley fever and lassa viruses. antibodies against ebola virus, particularly the zaire strain, were detected in all regions and were, over-all, more abundant than antibodies against the other antigens. ebola and marburg a ...19836419422
physicochemical properties of marburg virus: evidence for three distinct virus strains and their relationship to ebola virus.the physicochemical and antigenic properties of three groups of marburg (mbg) virus isolates, separated temporally and geographically, were compared to each other and to another member of the same family, ebola (ebo) virus. each mbg isolate contained seven virion proteins, one of which was a glycosylated surface protein. peptide mapping of glycoproteins, nucleoproteins (np) and viral structural protein (vp40) demonstrated extensive sequence conservation in the proteins of viruses isolated over a ...19883404120
[indirect immunoenzyme method for the laboratory diagnosis of lassa and ebola hemorrhagic fevers].conditions for performing solid-phase indirect enzyme-immunoassay (speia) for the detection of lassa and ebola virus antigens and antibodies to them using horseradish peroxidase-labeled antispecific globulins were developed. the method is highly sensitive, specific, and reproducible. by this method, antigens of lassa and ebola viruses could be detected in tissue culture fluid of the infected cell cultures and in animal organ suspensions. detection of antibodies to lassa and ebola viruses in huma ...19863524001
[serological study of the virus responsible for hemorrhagic fever in an urban population of cameroon].a sero-epidemiological study of hemorrhagic fever viruses in a urban population of cameroon. the authors report the results of a sero-epidemiological survey undertaken in a urban population of cameroon and concerning congo, rift (rvf), lassa, ebola, marburg and yellow fever viruses. on 375 human sera tested, 1.06% show antibodies against rvf virus and 1.87% are positive for anti-ebola antibodies thus yielding evidence that these two viruses are present in this area of cameroon. 33.75% have antib ...19883064937
no evidence of lav infection in the republic of liberia, west africa, in the year 1973.sera collected 13 years ago from 592 residents of the republic of liberia have been tested for antibodies to lav polypeptides. 7 sera were positive by elisa using two commercially available test kits whereas immunoblotting did not confirm antibodies specific for lav.19863015288
hemorrhagic fever virus infections in an isolated rainforest area of central liberia. limitations of the indirect immunofluorescence slide test for antibody screening in africa.serum samples from 119 healthy individuals and 106 epilepsy patients inhabiting grand bassa county, liberia, were tested for antibodies to hemorrhagic fever viruses (hfv) by indirect immunofluorescence. e6 vero cells infected with lassa fever virus (las), rift valley fever virus (rvf), congo hemorrhagic fever virus (con), marburg virus (mbg) and the ebola (ebo) virus strains mayinga (may) and boniface (bon) were used as antigen. to obtain reproducible and specific test results sera had to be abs ...19863092415
a comparison of indirect immunofluorescence and electron microscopy for the diagnosis of some haemorrhagic viruses in cell cultures.yellow fever, dengue (types 1, 2 and 4), chikungunya, rift valley fever, ebola, marburg, and lassa viruses were inoculated into susceptible cell cultures and daily investigated by indirect immunofluorescence (ifa) and electron microscopy (em) with a view to achieve an early detection-identification of these agents. compared to the other cell lines tested (vero, bhk-21 and aedes albopictus), cv-1 cells were found to be more sensitive. viral antigens were detected by ifa from a few hours post inoc ...19817024293
[current serologic data on viral hemorrhagic fevers in the central african republic].during the years 1984-1985, 1,528 serum samples were taken through out the car. of these sera, 319 (20.8%) contained anti-filoviridae antibodies (ebola, marburg). this figure is higher than those found in cameroon, sudan, gabon and zaïre. three zones of the country are particularly exposed, the north-east where the population is in the contact with sudan ebola, the south-east where it is in contact with zaïre ebola, and the south-west where it is in contact with sudan ebola. the authors believe ...19873607998
descriptive analysis of ebola virus proteins.the virion proteins of two strains of ebola virus were compared by sds-polyacrylamide gel electrophoresis (page) and radioimmunoprecipitation (rip). seven virion proteins were described; an l (180k), gp (125k), np (104k), vp40 (40k), vp35 (35k), vp30 (30k), and vp24 (24k). the rnp complex of the virus contained the l, the np, and vp30, with vp35 in loose association with them. the gp was the major spike protein, with vp40 and vp24 making up the remaining protein content of the multilayered envel ...19854060597
inactivating lassa and marburg/ebola viruses. 19826123862
modifications to indirect immunofluorescence tests on lassa, marburg, and ebola material. 19836131336
pathophysiology of shock and hemorrhage in a fulminating viral infection (ebola).eleven rhesus monkeys were monitored intensively during experimental infection with ebola virus. prominent neutrophilia with left shift and lymphopenia were the earliest abnormalities and were statistically significant by day 4 (p less than .02 and p less than .01, respectively). by day 4 falls in platelet counts were not statistically significant, whereas in vitro platelet aggregation was markedly depressed, progressing rapidly to complete failure by the time of maximum illness. intraplatelet p ...19854045253
lack of cross reactivity of rhabdovirus antibodies with marburg and ebola antigens in the indirect immunofluorescent antibody test. 19826179483
exotic viral diseases.marburg virus disease, lassa fever, monkeypox, and ebola virus diseases of humans have all been recognized since 1967. these are examples of some of the exotic virus diseases which through importation may present a potential public health problem in the united states. some of these viruses are also highly hazardous to laboratory and medical personnel. this paper is a review of the general characteristics, the epidemiology, and laboratory diagnosis of the exotic viruses which have been described ...19806246685
a probable case of ebola virus haemorrhagic fever in kenya. 19836671431
ultrastructural pathology of experimental ebola haemorrhagic fever virus infection.the organs of monkeys infected with ebola haemorrhagic fever were examined by light and electron microscopy during the acute stage of the disease. the virus caused focal coagulative necrosis in the liver, spleen, kidney, lung and testis and widespread mild vascular damage. in the brain there was intense congestion, with erythrocyte 'sludging', but no inflammatory reaction. there was significant injury to the microvasculature in all organs. virus replicated in endothelial cytoplasm causing focal ...19854067737
inactivated vaccine for ebola virus efficacious in guineapig model. 19806108462
exotic infectious diseases: marburg/ebola/haemorrhagic fevers. 19806770413
ebola virus infection in man: a serological and epidemiological survey in the cameroons.the presence of antibodies to ebola virus among 1,517 apparently healthy persons in five regions of the cameroons was tested using indirect immunofluorescence. a positive rate of 9.7% was found, confirming that the virus circulates in the absence of clinical cases. highest rates were found among pygmies, young adults, and rain forest farmers.19836650749
biologic differences between strains of ebola virus from zaire and sudan. 19836827142
antigenic analysis of strains of ebola virus: identification of two ebola virus serotypes.a sensitive radioimmunoassay has been adapted for ebola virus antigens and antibodies to them. it uses 125i-labeled staphylococcal protein a and a specially designed filter manifold. the assay is applicable to the sera of humans and to a wide range of animal sera. virus isolates from two discrete outbreaks of ebola hemorrhagic fever that occurred in 1976 were shown by this assay to be antigenically distinct. this lack of identity was further confirmed by cross-absorbing antisera to each isolate ...19836827143
evidence for two subtypes of ebola virus based on oligonucleotide mapping of rna.ebola viruses isolated during outbreaks of acute hemorrhagic fever in africa from 1976 to 1979 were examined by t1 oligonucleotide mapping of virion rna. two ebola virus subtypes distinguishable by their oligonucleotide patterns were involved in the outbreaks of the disease during this three-year period. the first type was isolated in zaire in 1976 and again in 1977; the second type caused outbreaks in sudan in 1976 and again in 1979. oligonucleotide patterns of the two groups of ebola viruses ( ...19836827144
comparative analysis of the structural polypeptides of ebola viruses from sudan and zaire.polypeptide structural analyses were performed by tryptic peptide mapping to assess the relationship between isolates of ebola virus obtained in sudan and zaire. the results of these analyses indicate (1) that the sudan and zaire isolates are unique viral agents, (2) that multiple isolates within each group bear close resemblance to one another, (3) that suggestive evidence exists of conservation of homologous structure in the vp-2 (virion protein no. 2) nucleocapsid proteins of these viruses, a ...19836827145
viral haemorrhagic fever surveillance in kenya, 1980-1981.following two cases of marburg virus disease in kenya in 1980, viral haemorrhagic fever surveillance was undertaken in western kenya. over a 21-month period investigations, including virus isolation attempts, patient and contact serology, visits to areas where suspected cases occurred, interviewing family members and neighbours of suspected cases and following up any additional illnesses in these areas, were carried out. during the study two cases were found that were likely to have been ebola h ...19836684336
antibody to ebola virus in guinea pigs: tandala, zaire.a case-control study was conducted to investigate the findings of antibody to ebola virus in the serum of a guinea pig from tandala, zaire. case households, defined by the possession of one or more guinea pigs, were compared to neighboring households without guinea pigs. seven (5.1%) of 138 samples of human sera and 36 (26%) of 138 samples of guinea pig sera had antibody to ebola virus. there was no clustering of seropositivity among humans or guinea pigs within households, nor was there any ass ...19826750007
marburg, ebola and rift valley fever virus antibodies in east african primates.sera from 464 primates held at four institutes in kenya were tested by indirect immunofluorescence for the presence of antibodies against marburg, ebola, congo haemorrhagic fever, rift valley fever and lassa viruses. four of 136 vervet monkeys were positive for marburg virus antibodies and three of 184 baboons had antibodies against ebola virus. one baboon was positive for marburg virus antibodies. two vervet monkeys, three baboons and one grivet monkey (of 56 tested) had antibodies against rift ...19826810518
[preliminary note on the presence of antibodies to ebola virus in the human population in the eastern part of the central african republic].the authors reported a preliminary serological survey on ebola virus infection in central african republic. they have tested 499 sera samples by using indirect immunofluorescent technique. the positivity with ebola antigen was 3,4% (17 cases). it has been found a high antibody titre (greater than or equal to 1/64) with 3 sera, which reflects a possible recent contact with ebola virus.19807014009
preparation of polyvalent viral immunofluorescent intracellular antigens and use in human serosurveys.a method is described for preparation of polyvalent antigens for use in rapid screening for immunofluorescent antibodies to lassa, marburg, and ebola viruses. the technique uses mixtures of specifically infected vero cells placed on teflon-templated microscopy slides. it was found to be as sensitive as the use of monovalent antigens for detection and quantitation of antibodies to these highly hazardous human pathogens.19817031084
plaque assay for ebola virus.a plaque assay for ebola virus is reported. the procedure has real potential for future research, although it is less sensitive than indirect fluorescent-antibody and mouse inoculation tests.19817014628
marburg and ebola virus antibodies in kenyan primates. 19816113374
inactivation of lassa, marburg, and ebola viruses by gamma irradiation.because of the cumbersome conditions experienced in a maximum containment laboratory, methods for inactivating highly pathogenic viruses were investigated. the infectivity of lassa, marburg, and ebola viruses was inactivated without altering the immunological activity after radiation with co60 gamma rays. at 4 degrees c, lassa virus was the most difficult to inactivate with a rate of 5.3 x 10(-6) log 50% tissue culture infective dose per rad of co60 radiation, as compared with 6.8 x 10(-6) log 5 ...19827153317
conservation of the 3' terminal nucleotide sequences of ebola and marburg virus.the 3' rna base sequences of several marburg (mbg) and ebola (ebo) virus isolates have been determined. a comparison of these 3' terminal noncoding sequences with those of other negative strand rna viruses suggests a unique phylogenic niche for marburg and ebola viruses. the translation initiation site and 35 n-terminal amino acids of the 3' proximal coding gene of a zaire strain of ebola virus was predicted. in addition, putative leader rna sequences preceding the first gene are discussed in te ...19863946083
ecology of ebola virus: a first clue? 19817017023
use of betapropionolactone inactivated ebola, marburg and lassa intracellular antigens in immunofluorescent antibody assay. 19827049096
haemorrhagic fever in gabon. i. incidence of lassa, ebola and marburg viruses in haut-ogooué.a serological enquiry aimed at determining the incidence of infection with lassa, ebola and marburg viruses was conducted on the human population of the region of haut-ogooué (gabon) and on primates. the results, obtained by the indirect immunofluorescence technique, showed that more than 6% of the human population had had contact with ebola virus but no antibodies against marburg or lassa viruses were found. most sera reacted to an ebola antigen from a zairian strain, but showed little or no re ...19827164137
ebola virus disease in southern sudan: hospital dissemination and intrafamilial spread.between 31 july and 6 october 1979, 34 cases of ebola virus disease (22 of which were fatal) occurred among five families in a rural district of southern sudan; the disease was introduced into four of the families from a local hospital. chains of secondary spread within the family units, accounting for 29 cases resulted from direct physical contact with an infected person. among all persons with such contact in the family setting, those who provided nursing care had a 5.1-fold increased risk of ...19836370486
inactivation of ebola virus with 60co irradiation. 19817217722
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