| venezuelan haemorrhagic fever. | an outbreak of severe haemorrhagic illness began in the municipality of guanarito, portuguesa state, venezuela, in september, 1989. subsequent detailed study of 15 cases confirmed the presence of a new viral disease, designated venezuelan haemorrhagic fever. characteristic features are fever, toxicity, headache, arthralgia, diarrhoea, conjunctivitis, pharyngitis, leucopenia, thrombocytopenia, and haemorrhagic manifestations. other features include facial oedema, cervical lymphadenopathy, nausea/ ... | 1991 | 1681354 |
| molecular phylogeny of guanarito virus, an emerging arenavirus affecting humans. | the nucleotide sequence of a portion of the nucleocapsid (n) gene of the guanarito virus prototype strain (inh-95551) has been determined. it was obtained by direct rna and polymerase chain reaction (pcr) fragment sequencing of the 3' end of the small (s) rna fragment. a comparison of this 782-nucleotide segment was done with the known homologous gene sequences of five other arenaviruses: junin, machupo, tacaribe, pichinde, and lymphocytic choriomeningitis (lcm). phylogenetic analysis of the n g ... | 1995 | 7542842 |
| description of guanarito virus (arenaviridae: arenavirus), the etiologic agent of venezuelan hemorrhagic fever. | this paper characterizes guanarito virus, the etiologic agent of venezuelan hemorrhagic fever. based on its morphology and antigenic properties, guanarito virus appears to be a new member of the tacaribe complex of the genus arenavirus, family arenaviridae. complement fixation and indirect fluorescent antibody tests showed that guanarito virus and its antiserum are broadly cross-reactive with other members of the tacaribe complex, but it can be differentiated from other members of the complex by ... | 1994 | 8166352 |
| field studies on the epidemiology of venezuelan hemorrhagic fever: implication of the cotton rat sigmodon alstoni as the probable rodent reservoir. | during february 1992, field studies on the epidemiology of venezuelan hemorrhagic fever (vhf) were carried out in a rural area of portuguesa state in central venezuela. the objective of this work was to determine the prevalence of infection with guanarito virus, the etiologic agent of vhf, among wild rodents and humans living within an endemic focus of the disease. a total of 234 rodents, representing nine different species, were collected and their spleens were cultured for virus. thirty-one gu ... | 1993 | 8395143 |
| genetic characterization and phylogeny of sabiá virus, an emergent pathogen in brazil. | sabiá virus, one of five arenaviruses from south america known to cause hemorrhagic fever in humans, emerged in 1990 when it was isolated from a fatal case in sao paulo, brazil. subsequently, it has caused two laboratory-acquired infections. its natural distribution and host are still unknown. using viral rna and multiple polymerase chain reaction products as templates, the nucleotide sequence of the small (s) rna segment of sabiá virus, which codes for the nucleocapsid (n) and glycoprotein prec ... | 1996 | 8661442 |
| isolation and characterization of pirital virus, a newly discovered south american arenavirus. | specific rodent species are principal hosts for each of the well-characterized members of the virus family arenaviridae. guanarito virus (arenaviridae) is the etiologic agent of venezuelan hemorrhagic fever. a previous study on the epidemiology of venezuelan hemorrhagic fever revealed extensive arenavirus infection (presumed to be caused by guanarito virus) in two rodent species. sigmodon alstoni and zygodontomys brevicauda, collected from the region of venezuela in which the disease is endemic. ... | 1997 | 9180606 |
| venezuelan hemorrhagic fever: clinical and epidemiological studies of 165 cases. | epidemiological and clinical data are presented on 165 cases of venezuelan hemorrhagic fever (vhf), a newly emerging viral zoonosis caused by guanarito virus (of the family arenaviridae). the disease is endemic in a relatively circumscribed area of central venezuela. since its first recognition in 1989, the incidence of vhf has peaked each year between november and january, during the period of major agricultural activity in the region of endemicity. the majority of cases have involved male agri ... | 1998 | 9502447 |
| natural rodent host associations of guanarito and pirital viruses (family arenaviridae) in central venezuela. | the objective of this study was to elucidate the natural rodent host relationships of guanarito and pirital viruses (family arenaviridae) in the plains of central venezuela. ninety-two arenavirus isolates from 607 animals, representing 10 different rodent species, were characterized to the level of serotype. the 92 isolates comprised 19 guanarito virus strains and 73 pirital virus strains. the 19 guanarito virus isolates were from zygodontomys brevicauda; 72 (98.6%) of the 73 pirital virus isola ... | 1999 | 10463688 |
| experimental infection of the cane mouse zygodontomys brevicauda (family muridae) with guanarito virus (arenaviridae), the etiologic agent of venezuelan hemorrhagic fever. | chronic infections in specific rodents appear to be crucial to the long-term persistence of arenaviruses in nature. the cane mouse, zygodontomys brevicauda, is a natural host of guanarito virus (family arenaviridae), the etiologic agent of venezuelan hemorrhagic fever. the purpose of this study was to elucidate the natural history of guanarito virus infection in z. brevicauda. thirty-nine laboratory-reared cane mice each were inoculated subcutaneously with 3.0 log10 plaque-forming units of the g ... | 1999 | 10479119 |
| guanarito virus (arenaviridae) isolates from endemic and outlying localities in venezuela: sequence comparisons among and within strains isolated from venezuelan hemorrhagic fever patients and rodents. | despite intensive surveillance, venezuelan hemorrhagic fever (vhf), caused by guanarito (gto) virus, has been detected in only a small region of western venezuela. to determine whether vhf is associated with a particular regional gto virus strain(s), 29 isolates from rodents and humans throughout the surrounding regions were analyzed by partial sequencing of the nucleocapsid protein gene. phylogenetic trees delineated nine distinct gto genotypes that differ by 4-17% in nucleotides and up to 9% i ... | 2000 | 10612673 |
| new world arenavirus clade c, but not clade a and b viruses, utilizes alpha-dystroglycan as its major receptor. | alpha-dystroglycan (alpha-dg) has been identified as a major receptor for lymphocytic choriomeningitis virus (lcmv) and lassa virus, two old world arenaviruses. the situation with new world arenaviruses is less clear: previous studies demonstrated that oliveros virus also exhibited high-affinity binding to alpha-dg but that guanarito virus did not. to extend these initial studies, several additional old and new world arenaviruses were screened for entry into mouse embryonic stem cells possessing ... | 2002 | 11967329 |
| phylogeny of the venezuelan arenaviruses. | guanarito virus (the etiologic agent of venezuelan hemorrhagic fever, vhf) and pirital virus coexist in the region of venezuela in which venezuelan hemorrhagic fever is endemic. the purpose of this study was to extend our knowledge of the evolutionary relationship between these two arenaviruses. we determined that the large genomic segments of guanarito virus and pirital virus are similar in size and identical in structural organization to the large genomic segments of other south american arena ... | 2004 | 15084402 |
| establishment of conventional and fluorescence resonance energy transfer-based real-time pcr assays for detection of pathogenic new world arenaviruses. | five of the known arenaviruses cause viral hemorrhagic fever in humans and are classified as biosafety level 4 pathogens. four of the viruses, namely junin, guanarito, machupo, and sabia, belong to clade b of new world arenaviruses that also comprises the nonpathogenic viruses tacaribe, cupixi, and amapari. | 2005 | 15722028 |
| hantavirus and arenavirus antibodies in persons with occupational rodent exposure. | rodents are the principal hosts of sin nombre virus, 4 other hantaviruses known to cause hantavirus pulmonary syndrome in north america, and the 3 north american arenaviruses. serum samples from 757 persons who had worked with rodents in north america and handled neotomine or sigmodontine rodents were tested for antibodies against sin nombre virus, whitewater arroyo virus, guanarito virus, and lymphocytic choriomeningitis virus. antibodies against sin nombre virus were found in 4 persons, agains ... | 2007 | 17553266 |
| cell entry by human pathogenic arenaviruses. | the arenaviruses lassa virus (lasv) in africa and machupo (macv), guanarito (gtov) and junin viruses (junv) in south america cause severe haemorrhagic fevers in humans with fatality rates of 15-35%. the present review focuses on the first steps of infection with human pathogenic arenaviruses, the interaction with their cellular receptor molecules and subsequent entry into the host cell. while similarities exist in genomic organization, structure and clinical disease caused by pathogenic old worl ... | 2008 | 18182084 |
| receptor determinants of zoonotic transmission of new world hemorrhagic fever arenaviruses. | transferrin receptor 1 (tfr1) is a cellular receptor for the new world hemorrhagic fever arenaviruses machupo (macv), junín (junv), and guanarito (gtov). each of these viruses is specifically adapted to a distinct rodent host species, but all cause human disease. here we compare the ability of these viruses to use various mammalian transferrin receptor 1 (tfr1) orthologs, including those of the south american rodents that serve as reservoirs for macv, junv, and gtov (calomys callosus, calomys mu ... | 2008 | 18268337 |
| site 1 protease is required for proteolytic processing of the glycoproteins of the south american hemorrhagic fever viruses junin, machupo, and guanarito. | the cellular proprotein convertase site 1 protease (s1p) has been implicated in the proteolytic processing of the glycoproteins (gps) of old world arenaviruses. here we report that s1p is also involved in the processing of the gps of the genetically more-distant south american hemorrhagic fever viruses guanarito, machupo, and junin. efficient cleavage of guanarito virus gp, whose protease recognition sites deviate from the reported s1p consensus sequence, indicates a broader specificity of s1p t ... | 2008 | 18400865 |
| genetic diversity between and within the arenavirus species indigenous to western venezuela. | the results of analyses of z, rna-dependent rna polymerase, glycoprotein precursor, and nucleocapsid protein gene sequence data suggested that guanarito virus was the most common cause of venezuelan hemorrhagic fever in a 7-year period in the 1990s and that the evolution of pirital virus in association with sigmodon alstoni (alston's cotton rat) has occurred at a significantly higher rate than the evolution of guanarito virus in association with zygodontomys brevicauda (short-tailed cane mouse) ... | 2008 | 18586298 |
| models for an arenavirus infection in a rodent population: consequences of horizontal, vertical and sexual transmission. | arenaviruses are associated with rodent-transmitted diseases in humans. five arenaviruses are known to cause human illness: lassa virus, junin virus, machupo virus, guanarito virus and sabia virus. in this investigation, we model the spread of machupo virus in its rodent host calomys callosus. machupo virus infection in humans is known as bolivian hemorrhagic fever (bhf) which has a mortality rate of approximately 5-30% [31]. machupo virus is transmitted among rodents through horizontal (direct ... | 2008 | 19278272 |
| characterization of monoclonal antibodies to junin virus nucleocapsid protein and application to the diagnosis of hemorrhagic fever caused by south american arenaviruses. | junin virus (junv), machupo virus, guanarito virus, sabia virus, and chapare virus are members of new world arenavirus clade b and are the etiological agents of viral hemorrhagic fevers that occur in south america. in this study, we produced three monoclonal antibodies (mabs) to the recombinant nucleocapsid protein of junv, designated c6-9, c11-12, and e4-2. the specificity of these mabs was examined by enzyme-linked immunosorbent assay (elisa), indirect immunofluorescence assay, and an epitope- ... | 2009 | 19553554 |
| investigation of clade b new world arenavirus tropism by using chimeric gp1 proteins. | clade b of the new world arenaviruses contains both pathogenic and nonpathogenic members, whose surface glycoproteins (gps) are characterized by different abilities to use the human transferrin receptor type 1 (htfr1) protein as a receptor. using closely related pairs of pathogenic and nonpathogenic viruses, we investigated the determinants of the gp1 subunit that confer these different characteristics. we identified a central region (residues 85 to 221) in the guanarito virus gp1 that was suffi ... | 2010 | 19889757 |
| the role of the vascular endothelium in arenavirus haemorrhagic fevers. | viral haemorrhagic fevers (vhf) caused by arenaviruses are among the most devastating emerging human diseases. the most important pathogen among the arenaviruses is lassa virus (lasv), the causative agent of lassa fever that is endemic to west africa. on the south american continent, the new world arenavirus junin virus (junv), machupo (macv), guanarito (gtov), and sabia virus (sabv) have emerged as causative agents of severe vhfs. clinical and experimental studies on arenavirus vhf have reveale ... | 2009 | 19967131 |
| z proteins of new world arenaviruses bind rig-i and interfere with type i interferon induction. | the retinoic acid-inducible gene i product (rig-i) is a cellular sensor of rna virus infection that regulates the cellular beta interferon (ifn-beta) response. the nucleoproteins (np) of arenaviruses are reported to antagonize the ifn response by inhibiting interferon regulatory factor 3 (irf-3). here, we demonstrate that the z proteins of four new world (nw) arenaviruses, guanarito virus (gtov), junin virus (junv), machupo virus (mavc), and sabia virus (sabv), bind to rig-i, resulting in downre ... | 2010 | 20007272 |
| a multivalent vaccination strategy for the prevention of old world arenavirus infection in humans. | arenaviruses cause severe human disease ranging from aseptic meningitis following lymphocytic choriomeningitis virus (lcmv) infection to hemorrhagic fever syndromes following infection with guanarito virus (gtov), junin virus (junv), lassa virus (lasv), machupo virus (macv), sabia virus (sabv), or whitewater arroyo virus (wwav). cellular immunity, chiefly the cd8(+) t-cell response, plays a critical role in providing protective immunity following infection with the old world arenaviruses lasv an ... | 2010 | 20668086 |
| t-705 (favipiravir) inhibition of arenavirus replication in cell culture. | a number of new world arenaviruses (junín [junv], machupo [macv], and guanarito [gtov] viruses) can cause human disease ranging from mild febrile illness to a severe and often fatal hemorrhagic fever syndrome. these highly pathogenic viruses and the old world lassa fever virus pose a significant threat to public health and national security. the only licensed antiviral agent with activity against these viruses, ribavirin, has had mixed success in treating severe arenaviral disease and is associa ... | 2010 | 21115797 |
| medical microbiology | the hallmark of arenaviruses is their tendency to cause persistent silent infections in their natural hosts (rodents) and severe, often lethal, disseminated disease in humans. arenaviruses are pleomorphic enveloped particles that contain two rna segments of virus origin and ribosome-like components. suitable conditions for transmission of virus to humans occur in areas where humans come in contact with rodent urine that contains virus. persistent viremia and viruria in rodents result from a slow ... | 1996 | 21413313 |
| antibody to arenaviruses in rodents, caribbean colombia. | to the editor: the approximately 20 recognized arenaviruses in the americas are hosted by rodents of the family cricetidae; 1 exception may be hosted by a bat (genus artibeus, family phyllostomidae) (1). pichindé virus, hosted by oryzomys albigularis, was described from animals in the pichindé valley near cali, colombia (2), and antibody reactive to pichindé virus was found in 2 of 82 serum samples from humans in the same area. no studies of arenavirus infection in rodents or humans have been co ... | 2011 | 21762602 |
| transmission of guanarito and pirital viruses among wild rodents, venezuela. | samples from rodents captured on a farm in venezuela in february 1997 were tested for arenavirus, antibody against guanarito virus (gtov), and antibody against pirital virus (pirv). thirty-one (48.4%) of 64 short-tailed cane mice (zygodontomys brevicauda) were infected with gtov, 1 alston's cotton rat (sigmodon alstoni) was infected with gtov, and 36 (64.3%) of 56 other alston's cotton rats were infected with pirv. the results of analyses of field and laboratory data suggested that horizontal tr ... | 2011 | 22172205 |
| glycoprotein-specific antibodies produced by dna vaccination protect guinea pigs from lethal argentine and venezuelan hemorrhagic fever. | several members of the arenaviridae can cause acute febrile diseases in humans, often resulting in lethality. the use of convalescent-phase human plasma is an effective treatment in humans infected with arenaviruses, particularly species found in south america. despite this, little work has focused on developing potent and defined immunotherapeutics against arenaviruses. in the present study, we produced arenavirus neutralizing antibodies by dna vaccination of rabbits with plasmids encoding the ... | 2016 | 26792737 |
| human hemorrhagic fever causing arenaviruses: molecular mechanisms contributing to virus virulence and disease pathogenesis. | arenaviruses include multiple human pathogens ranging from the low-risk lymphocytic choriomeningitis virus (lcmv) to highly virulent hemorrhagic fever (hf) causing viruses such as lassa (lasv), junin (junv), machupo (macv), lujo (lujv), sabia (sabv), guanarito (gtov), and chapare (chpv), for which there are limited preventative and therapeutic measures. why some arenaviruses can cause virulent human infections while others cannot, even though they are isolated from the same rodent hosts, is an e ... | 2015 | 26011826 |
| diseases of the central nervous system caused by lymphocytic choriomeningitis virus and other arenaviruses. | | 2014 | 25015511 |
| inhibition of arenavirus infection by a glycoprotein-derived peptide with a novel mechanism. | the family arenaviridae includes a number of viruses of public health importance, such as the category a hemorrhagic fever viruses lassa virus, junin virus, machupo virus, guanarito virus, and sabia virus. current chemotherapy for arenavirus infection is limited to the nucleoside analogue ribavirin, which is characterized by considerable toxicity and treatment failure. using pichinde virus as a model arenavirus, we attempted to design glycoprotein-derived fusion inhibitors similar to the fda-app ... | 2014 | 24850726 |
| crystal structure of venezuelan hemorrhagic fever virus fusion glycoprotein reveals a class 1 postfusion architecture with extensive glycosylation. | guanarito virus (gtov) is an emergent and deadly pathogen. we present the crystal structure of the glycosylated gtov fusion glycoprotein to 4.1-å resolution in the postfusion conformation. our structure reveals a classical six-helix bundle and presents direct verification that new world arenaviruses exhibit class i viral membrane fusion machinery. the structure provides visualization of an n-linked glycocalyx coat, and consideration of glycan dynamics reveals extensive coverage of the underlying ... | 2013 | 24049182 |
| drug discovery technologies and strategies for machupo virus and other new world arenaviruses. | seven arenaviruses cause viral hemorrhagic fever in humans: the old world arenaviruses lassa and lujo, and the new world clade b arenaviruses machupo (macv), junín (junv), guanarito (gtov), sabiá (sabv), and chapare (chpv). all of these viruses are risk group 4 biosafety pathogens. macv causes human disease outbreak with high case-fatality rates. to date, at least 1,200 cases with ≈200 fatalities have been recorded. | 2012 | 22607481 |
| [a prototype of oligonucleotide microarray for detection of pathogens relating to arena- and filoviridae families]. | a prototype of oligonucleotide microarray for detection of lassa, junin, machupo, guanarito viruses (arenaviridae family), ebola and marburg viruses (filoviridae family) was presented. an original approach founded on virus proteins (nucleocapsid protein for junin, guanarito, machupo viruses and rna-dependent rna-polymerase for lassa, ebola and marburg viruses) amino acid sequences analysis with subsequent transform of revealed unique peptides into due sets of oligonucleotides was used to design ... | 2015 | 26050472 |
| an attenuated machupo virus with a disrupted l-segment intergenic region protects guinea pigs against lethal guanarito virus infection. | machupo virus (macv) is a new world (nw) arenavirus and causative agent of bolivian hemorrhagic fever (hf). here, we identified a variant of macv strain carvallo termed car(91) that was attenuated in guinea pigs. infection of guinea pigs with an earlier passage of carvallo, termed car(68), resulted in a lethal disease with a 63% mortality rate. sequencing analysis revealed that compared to car(68), car(91) had a 35 nucleotide (nt) deletion and a point mutation within the l-segment intergenic reg ... | 2017 | 28680057 |
| [first evidence of lymphocytic choriomeningitis virus (arenavirus) infection in mus musculus rodents captured in the urban area of the municipality of sincelejo, sucre, colombia]. | the lymphocytic choriomeningitis virus is an old world arenavirus that infects mus musculus, and can cause congenital hydrocephalus, chorioretinitis and multisystemic failure in transplant human recipients. although the disease has not been clinically diagnosed in colombia yet, there have been reports of infection with the pichindé virus in rodents from cauca and valle del cauca departments, and with the guanarito virus in rodents from córdoba department. | 2017 | 28527269 |
| a single mutation (v64g) within the ring domain of z attenuates junin virus. | junin virus (junv) is a new world arenavirus that is the causative agent of argentine hemorrhagic fever (ahf). candid#1 (can) is a live-attenuated vaccine strain of junv that since its introduction has resulted in a marked decrease in ahf incidence within the endemic regions of the pampas in argentina. originally, the viral determinants and mechanisms of can attenuation were not well understood. recent work has identified the glycoprotein as the major attenuating factor for can. the establishmen ... | 2020 | 32976538 |