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1.
Open Forum Infect Dis ; 5(10): ofy239, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30386807

RESUMO

BACKGROUND: The Eternal Love Winning Africa (ELWA) Clinic was the first clinic to provide free, comprehensive care to Ebola virus disease (EVD) survivors in Liberia. The objectives of this analysis were to describe the demographics and symptoms of EVD survivors at ELWA from January 2015 through March 2017 and to identify risk factors for development of sequelae. METHODS: Patients' demographic and clinical information was collected by chart review in June 2016 and March 2017. Associations with clinical sequelae were analyzed using the chi-square test, t test, and multivariate logistic regression. RESULTS: From January 2015 to March 2017, 329 EVD survivors were evaluated at ELWA. Most survivors experienced myalgia/arthralgia (73%; n = 239) and headache (53%; n = 173). The length of time from Ebola Treatment Unit (ETU) discharge to first clinic visit ranged from 0 to 30 months. Many visits (30%) occurred 24 or more months after ETU discharge. The proportion of visits for headache, weight loss, joint pain, visual problems, insomnia, fatigue, memory loss, decreased libido, depression, and uveitis decreased over time. More men than women had visits for depression; however, these differences were not significant. Symptom prevalence differed in adults and children; significantly more adults experienced myalgia/arthralgia (77% vs 44%), visual problems (41% vs 12%), post-EVD-related musculoskeletal pain (42% vs 15%), and insomnia (17% vs 2%). CONCLUSIONS: EVD survivors frequented ELWA for EVD-related symptoms many months after ETU discharge, indicating a long-term need for care. Reported symptoms changed over time, which may reflect eventual resolution of some sequelae.

2.
Genome Announc ; 6(12)2018 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-29567745

RESUMO

We report here the complete genome sequences for all three segments of the New York hantavirus (New York 1). This is the first reported L segment sequence for hantaviruses maintained in Peromyscus spp. endemic to the eastern United States and Canada.

3.
Virology ; 442(2): 97-100, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23711383

RESUMO

In 2012, an unprecedented number of four distinct, partially overlapping filovirus-associated viral hemorrhagic fever outbreaks were detected in equatorial Africa. Analysis of complete virus genome sequences confirmed the reemergence of Sudan virus and Marburg virus in Uganda, and the first emergence of Bundibugyo virus in the Democratic Republic of the Congo.


Assuntos
Surtos de Doenças , Infecções por Filoviridae/epidemiologia , Filoviridae/genética , Filoviridae/isolamento & purificação , Genoma Viral , Febres Hemorrágicas Virais/epidemiologia , RNA Viral/genética , República Democrática do Congo/epidemiologia , Filoviridae/classificação , Infecções por Filoviridae/virologia , Febres Hemorrágicas Virais/virologia , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA , Uganda/epidemiologia
4.
Intervirology ; 55(6): 488-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22572722

RESUMO

Surveillance work was initiated to study the presence of highly infectious diseases like Ebola-Reston, Marburg, Nipah and other possible viruses that are known to be found in the bat species and responsible for causing diseases in humans. A novel adenovirus was isolated from a common species of fruit bat (Rousettus leschenaultii) captured in Maharashtra State, India. Partial sequence analysis of the DNA polymerase gene shows this isolate to be a newly recognized member of the genus Mastadenovirus (family Adenoviridae), approximately 20% divergent at the nucleotide level from Japanese BatAdV, its closest known relative.


Assuntos
Infecções por Adenoviridae/veterinária , Quirópteros/virologia , Mastadenovirus/isolamento & purificação , Infecções por Adenoviridae/diagnóstico , Infecções por Adenoviridae/virologia , Animais , DNA Polimerase Dirigida por DNA/análise , DNA Polimerase Dirigida por DNA/genética , Índia , Mastadenovirus/classificação , Mastadenovirus/genética , RNA Viral/genética
5.
J Gen Virol ; 84(Pt 10): 2685-2689, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-13679602

RESUMO

A virus isolated from dead Chaerephon plicata bats collected near Kampot, Cambodia, was identified as a member of the family Bunyaviridae by electron microscopy. The only bunyavirus previously isolated from Chaerephon species bats in South-East Asia is Kaeng Khoi (KK) virus (genus Orthobunyavirus), detected in Thailand over 30 years earlier and implicated as a public health problem. Using RT-PCR, nucleotide sequences from the M RNA segment of several virus isolates from the Cambodian C. plicata bats were found to be almost identical and to differ from those of the prototype KK virus by only 2.6-3.2 %, despite the temporal and geographic separation of the viruses. These results identify the Cambodian bat viruses as KK virus, extend the known virus geographic range and document the first KK virus isolation in 30 years. These genetic data, together with earlier serologic data, show that KK viruses represent a distinct group within the genus Orthobunyavirus.


Assuntos
Infecções por Bunyaviridae/veterinária , Bunyaviridae/classificação , Bunyaviridae/isolamento & purificação , Quirópteros/virologia , Animais , Encéfalo/virologia , Bunyaviridae/genética , Bunyaviridae/patogenicidade , Infecções por Bunyaviridae/virologia , Camboja , Chlorocebus aethiops , Camundongos , Filogenia , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Vero
6.
J Gen Virol ; 83(Pt 9): 2117-2122, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12185264

RESUMO

Hantavirus pulmonary syndrome (HPS) has been recognized increasingly as a significant public health problem in South America since Andes virus was first discovered in Argentina. Here, the isolation of Andes virus is reported from an infected rodent captured in Argentina in close vicinity to the place of the first HPS case, AH1. The complete nucleotide sequences of the virus M segment, partial L segment and the termini of the S, M and L segment genome RNAs were determined. The Andes virus M RNA segment is 3671 nt in length and is predicted to encode a glycoprotein precursor 1138 aa in length; it generally resembles the other HPS-associated hantaviruses in its organization. Relative to the G1 glycoprotein of other HPS-associated hantaviruses, an additional potential glycosylation site was found but this is located in the predicted cytoplasmic domain and is therefore unlikely to be glycosylated. In phylogenetic analyses, Andes virus, together with the more related hantaviruses, represented a monophyletic lineage. The S-terminal nucleotides were conserved relative to other New World hantaviruses. The M and L segment RNA termini had short deletions in the region believed to contain the sequence and structural features necessary for initiation of virus RNA replication and transcription. Clinical manifestations of Andes virus infections range from fulminant respiratory disease with high lethality to mild course without sequelae. Andes virus has also been associated with person-to-person transmission. Accumulation of Andes virus genetic data will be essential for understanding the factors that regulate virus replication and transmission and to determine the pathogenesis of HPS.


Assuntos
Orthohantavírus/genética , RNA Viral/genética , Roedores/virologia , Animais , Clonagem Molecular , Variação Genética , Orthohantavírus/química , Orthohantavírus/isolamento & purificação , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral/química , Alinhamento de Sequência , Sequências Repetidas Terminais
7.
J Med Virol ; 66(4): 542-51, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11857535

RESUMO

In this study, two different hantaviruses, Puumala virus (PUUV) and Dobrava virus (DOBV), were demonstrated for the first time to coexist and cause hemorrhagic fever with renal syndrome (HFRS) in Croatia. Phylogenetic analysis showed some differences among the nucleotide sequences of PUUV originating from Dinara mountain, which was more closely related to Austrian PUUV than other Croatian PUUV from Mala Kapela mountain. More consistency was found among the Croatian DOBV. HFRS was verified in 85 of 201 suspected cases recorded in 1995 during the largest HFRS outbreak in Croatia. Most of these cases were soldiers. With the exception of the coastal region and islands, all of Croatia was found to be an area endemic for HFRS. A statistically significantly higher proportion of DOBV-infected patients had acute renal failure, visual disturbance, severe thrombocytopenia, and elevated levels of nonsegmented leukocytes, creatine, and total bilirubin. The prevalence of gastrointestinal and electrocardiography disorders also was greater in DOBV-infected patients. Interestingly, significantly more PUUV-infected patients had elevated systolic blood pressure on admission to the hospital. Further prospective studies are necessary to shed more light on differences in HFRS severity associated with PUU and DOB viruses.


Assuntos
Surtos de Doenças , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/fisiopatologia , Militares , Orthohantavírus/classificação , Virus Puumala/classificação , Adulto , Croácia/epidemiologia , Orthohantavírus/genética , Febre Hemorrágica com Síndrome Renal/virologia , Humanos , Masculino , Filogenia , Virus Puumala/genética , Análise de Sequência de DNA , Guerra
8.
Virology ; 286(2): 345-53, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11485402

RESUMO

Hantaviruses, family Bunyaviridae, are rodent-borne RNA viruses that can cause hantavirus pulmonary syndrome (HPS) in various regions of the Americas. A coevolutionary relationship exists between hantaviruses and their specific rodent reservoir hosts; the phylogeny of the viruses generally matches that of the rodents. There are several Peromyscus-borne hantaviruses, including Sin Nombre virus, the most common cause of HPS in North America. This report describes the genetic detection and characterization of a newly discovered Peromyscus boylii-borne virus, Limestone Canyon (LSC) virus, the most divergent member of the Peromyscus-borne hantaviruses to date. Analysis of a 1209-nucleotide region of the S segment of LSC virus showed it to be more closely related to hantaviruses found in harvest mice (Reithrodontomys megalotis and R. mexicanus) than to other Peromyscus-associated hantaviruses (Sin Nombre, New York, and Monongahela). Phylogenetic analysis of virtually the entire M genome segment (3489 nucleotides) of LSC virus revealed a similar picture in which LSC virus was found to be very distinct from other Peromyscus-associated viruses, but its exact relationship to the other Peromyscus-borne and the Reithrodontomys-borne viruses was not resolved. These results indicate that hantavirus host species-jumping events can occur by which a hantavirus may switch to, and become established in, a rodent host belonging to a different genus. P. boylii are present throughout the southwestern United States and central Mexico. More extensive screening of HPS patients by using RT-PCR assays will be necessary to determine if LSC virus can cause human disease.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Hantavirus/veterinária , Orthohantavírus/classificação , Orthohantavírus/genética , Peromyscus/virologia , Doenças dos Roedores/virologia , Animais , DNA Viral/análise , Orthohantavírus/imunologia , Infecções por Hantavirus/virologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
9.
Virus Res ; 75(1): 75-86, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11311430

RESUMO

In Canada, hantavirus infected deer mice (Peromyscus maniculatus) have been collected from British Columbia to Newfoundland. Partial sequencing of G1 and N protein encoding regions from Canadian Peromyscus maniculatus-borne hantaviruses demonstrated the existence of significant genotypic divergence among strains. Phylogenetic analysis showed that Sin Nombre (SN)-like viruses from eastern and western Canadian deer mice can be divided into at least two broad-based genogroups. Sequencing of mitochondrial DNA from infected deer mice originating from various eastern and western provinces showed that SN-like virus genogroups appeared to be associated with distinct haplotypes of mice. Sera from deer mice infected with eastern and western viral genotypes neutralized the Sin Nombre virus strain, Convict Creek 107, but not the New York 1 hantavirus. Despite the genetic heterogeneity of Canadian SN-like strains these hantaviruses do not appear to define unique hantavirus serotypes.


Assuntos
Proteínas do Capsídeo , Orthohantavírus/classificação , Peromyscus/virologia , Sequência de Aminoácidos , Animais , Canadá , Capsídeo/genética , Orthohantavírus/genética , Orthohantavírus/imunologia , Dados de Sequência Molecular , Testes de Neutralização , Filogenia , Alinhamento de Sequência , Proteínas do Core Viral/genética , Proteínas do Envelope Viral/genética
10.
Virology ; 291(2): 185-90, 2001 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11878887

RESUMO

In late 1997 and early 1998, a large outbreak of hemorrhagic fever occurred in East Africa. Clinical samples were collected in Kenya and southern Somalia, and 27 of 115 (23%) hemorrhagic fever patients tested showed evidence of acute infection with Rift Valley fever (RVF) virus as determined by IgM detection, virus isolation, detection of virus RNA by reverse transcription-polymerase chain reaction (RT-PCR), or immunohistochemistry. However, two patients (one from Kenya and the other from Somalia) whose illness met the hemorrhagic fever case definition yielded virus isolates that were not RVF. Electron microscopy suggested these two virus isolates were members of the family Bunyaviridae. RT-PCR primers were designed to detect bunyavirus RNA in these samples. Regions of the S and L segments of the two isolates were successfully amplified, and their nucleotide sequences exhibited nearly complete identity with Bunyamwera virus, a mosquito-borne virus not previously associated with severe human disease. Unexpectedly, the virus M segment appeared to be reassorted, as the sequences detected exhibited 32-33% nucleotide and 28% amino acid differences relative to the corresponding M segment sequence of Bunyamwera virus. The association of this reassortant bunyavirus, proposed name Garissa virus, with severe disease is supported by the detection of the virus RNA in acute-phase sera taken from 12 additional hemorrhagic fever cases in the region.


Assuntos
Vírus Bunyamwera/genética , Infecções por Bunyaviridae/virologia , Febres Hemorrágicas Virais/virologia , Vírus Reordenados/genética , Animais , Anticorpos Antivirais/sangue , Sequência de Bases , Vírus Bunyamwera/classificação , Vírus Bunyamwera/isolamento & purificação , Vírus Bunyamwera/ultraestrutura , Infecções por Bunyaviridae/epidemiologia , Infecções por Bunyaviridae/imunologia , Chlorocebus aethiops , Surtos de Doenças , Febres Hemorrágicas Virais/epidemiologia , Febres Hemorrágicas Virais/imunologia , Humanos , Quênia/epidemiologia , Dados de Sequência Molecular , Filogenia , RNA Viral/análise , Vírus Reordenados/classificação , Vírus Reordenados/isolamento & purificação , Vírus Reordenados/ultraestrutura , Recombinação Genética , Somália/epidemiologia , Células Vero
11.
Emerg Infect Dis ; 6(6): 616-21, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11076720

RESUMO

The first two recognized cases of rapidly fatal hantavirus pulmonary syndrome in Pennsylvania occurred within an 8-month period in 1997. Illness in the two patients was confirmed by immunohistochemical techniques on autopsy material. Reverse transcription-polymerase chain reaction analysis of tissue from one patient and environmentally associated Peromyscus leucopus (white-footed mouse) identified the Monongahela virus variant. Physicians should be vigilant for such Monongahela virus-associated cases in the eastern United States and Canada, particularly in the Appalachian region.


Assuntos
Infecções por Hantavirus/etiologia , Pneumopatias/etiologia , Orthohantavírus/classificação , Adulto , Animais , Feminino , Orthohantavírus/genética , Orthohantavírus/isolamento & purificação , Infecções por Hantavirus/patologia , Humanos , Pulmão/virologia , Masculino , Pennsylvania , Peromyscus/virologia
12.
Virology ; 277(1): 14-9, 2000 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-11062031

RESUMO

Hantavirus pulmonary syndrome (HPS), a severe respiratory disease with high mortality caused by rodent-borne hantaviruses, has previously been identified in the United States and Canada as well as central and southern South America. In late 1999 and early 2000, an outbreak of acute illness compatible with HPS was reported in Los Santos, Panama, with the death of 3 of the 12 (25%) suspected cases. Hantavirus-specific antibodies were detected in patient sera, and virus RNA was detected by reverse transcriptase-polymerase chain reaction. Sequence analysis of virus genome N-, G1-, and G2-encoding fragments showed this to be a novel hantavirus, Choclo virus. Serologic and virus genetic analyses of rodents trapped in the area showed Oligoryzomys fulvescens to be the likely reservoir for the HPS-associated Choclo virus. In addition, Zygodontomys brevicauda rodents were shown to harbor another genetically unique hantavirus, Calabazo virus.


Assuntos
Reservatórios de Doenças , Síndrome Pulmonar por Hantavirus/virologia , Orthohantavírus/classificação , Filogenia , Animais , Canadá , Primers do DNA , Genoma Viral , Orthohantavírus/genética , Orthohantavírus/isolamento & purificação , Síndrome Pulmonar por Hantavirus/classificação , Humanos , Nucleocapsídeo/genética , Panamá , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sorotipagem , América do Sul , Estados Unidos
14.
J Virol ; 74(15): 6992-7004, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10888638

RESUMO

The arenavirus Lassa virus causes Lassa fever, a viral hemorrhagic fever that is endemic in the countries of Nigeria, Sierra Leone, Liberia, and Guinea and perhaps elsewhere in West Africa. To determine the degree of genetic diversity among Lassa virus strains, partial nucleoprotein (NP) gene sequences were obtained from 54 strains and analyzed. Phylogenetic analyses showed that Lassa viruses comprise four lineages, three of which are found in Nigeria and the fourth in Guinea, Liberia, and Sierra Leone. Overall strain variation in the partial NP gene sequence was found to be as high as 27% at the nucleotide level and 15% at the amino acid level. Genetic distance among Lassa strains was found to correlate with geographic distance rather than time, and no evidence of a "molecular clock" was found. A method for amplifying and cloning full-length arenavirus S RNAs was developed and used to obtain the complete NP and glycoprotein gene (GP1 and GP2) sequences for two representative Nigerian strains of Lassa virus. Comparison of full-length gene sequences for four Lassa virus strains representing the four lineages showed that the NP gene (up to 23.8% nucleotide difference and 12.0% amino acid difference) is more variable than the glycoprotein genes. Although the evolutionary order of descent within Lassa virus strains was not completely resolved, the phylogenetic analyses of full-length NP, GP1, and GP2 gene sequences suggested that Nigerian strains of Lassa virus were ancestral to strains from Guinea, Liberia, and Sierra Leone. Compared to the New World arenaviruses, Lassa and the other Old World arenaviruses have either undergone a shorter period of diverisification or are evolving at a slower rate. This study represents the first large-scale examination of Lassa virus genetic variation.


Assuntos
Variação Genética , Febre Lassa/virologia , Vírus Lassa/genética , Nucleoproteínas/genética , Proteínas Virais/genética , África Ocidental , Animais , Arenaviridae/genética , Sequência de Bases , Evolução Molecular , Humanos , Febre Lassa/epidemiologia , Vírus Lassa/classificação , Vírus Lassa/isolamento & purificação , Dados de Sequência Molecular , Filogenia , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Proteínas do Envelope Viral/genética
15.
J Med Virol ; 60(2): 237-47, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10596027

RESUMO

Hantaviruses are rodent-borne viruses, and they, mainly the Hantaan (HTN) serotype, are the causative agents of a group of febrile nephropathies known as "hemorrhagic fever with renal syndrome (HFRS). " Despite the fact that HFRS is frequently reported in China, with an annual incidence of 50,000-100,000 cases, one puzzling observation that no local case of HFRS has been confirmed in Taiwan has yet to be explained. We hypothesized that the hantavirus strain prevailing in Taiwan mainly belongs to the mild strain, the Seoul (SEO) strain, and the absence of severe disease was related to the absence of HTN. To test these hypotheses, this epidemiologic study was performed, including a seroprevalence survey and phylogenetic analysis on hantavirus isolated from the rodent population trapped in major seaports, rural, and mountainous areas of Taiwan. This study also included rodents and viruses from two isolated islands, Kinmen and Matzu, which are geographically adjacent to the east coast of mainland China. There were a total of 5,461 rodents of 16 species captured, and R. norvegicus was the most common species, with an antibody prevalence much higher in international seaports (20%) than in rural regions (approximately 5%) and intermediate in some domestic seaports. By reverse transcriptase polymerase chain reaction (RT-PCR), 33.9% of the seropositive R. norvegicus were found to have amplifiable hantavirus sequences in their lung tissues, and subsequent phylogenetic analyses indicated that almost all hantavirus in Taiwan was most closely related to the prototype SEO strain, and no HTN strain was recovered from any rodent species indigenous to Taiwan. The seroprevalence of SEO infection in R. norvegicus on Kinmen and Matzu was also different from that in southern provinces of China but closely resembled that in seaports in Taiwan, and the SEO identified was genetically linked to Taiwanese SEO strains. These results substantiate our hypotheses, and suggest that the epidemiology of hantavirus infection in Taiwan are different from that in China, where the HTN and SEO strains and HFRS concurrently prevail.


Assuntos
Infecções por Hantavirus/veterinária , Orthohantavírus/isolamento & purificação , RNA Viral/análise , Doenças dos Roedores/epidemiologia , Animais , Reservatórios de Doenças , Ensaio de Imunoadsorção Enzimática , Geografia , Orthohantavírus/genética , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/virologia , Humanos , Filogenia , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Doenças dos Roedores/virologia , Roedores , Alinhamento de Sequência , Estudos Soroepidemiológicos , Taiwan/epidemiologia
16.
J Med Virol ; 59(4): 527-35, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10534737

RESUMO

Although hantavirus pulmonary syndrome (HPS) was discovered in North America in 1993, more recent investigations have shown that the disease is a much larger problem in South America, where a greater number of cases and HPS-associated viruses have now been detected. Here we describe the genetic investigation of three fatal HPS cases from Brazil, including a 1995 case in Castelo dos Sonhos (CAS) in the state of Mato Grosso and two 1996 cases in the counties of Araraquara (ARA) and Franca (FRA), in the state of São Paulo. Reverse transcription-polymerase chain reaction (RT-PCR) products representing fragments of the hantavirus N, G1, and G2 coding regions were amplified from patient acute-phase serum samples, and the nucleotide (nt) sequences (394, 259, and 139 nt, respectively) revealed high deduced amino acid sequence identity between ARA and FRA viruses (99.2%, 96.5%, and 100%, respectively). However, amino acid differences of up to 14.0% were observed when ARA and FRA virus sequences were compared with those of the geographically more distant CAS virus. Analysis of a 643-nt N coding region and a 1734-nt predominantly G2-encoding region of ARA and CAS virus genomes confirmed that these Brazilian viruses were distinct and monophyletic with previously characterized Argentinean hantaviruses, and suggested that Laguna Negra (LN) virus from Paraguay was ancestral to both the Brazilian and Argentinean viruses. The phylogenetic tree based on the N coding fragment also placed LN in a separate clade with Rio Mamore virus from Bolivia. At the amino acid level, ARA and CAS viruses appeared more closely related to the Argentinean viruses than they were to each other. Similarly, analysis of the diagnostic 139-nt G2 fragment showed that the Juquitiba virus detected in a 1993 fatal HPS case close to São Paulo city, Brazil was closer to Argentinean viruses than to ARA or CAS viruses. These data indicate that at least three different hantavirus genetic lineages are associated with Brazilian HPS cases.


Assuntos
Síndrome Pulmonar por Hantavirus/virologia , Orthohantavírus/genética , Anticorpos Antivirais/sangue , Brasil , DNA Viral/análise , Evolução Fatal , Feminino , Orthohantavírus/classificação , Orthohantavírus/isolamento & purificação , Humanos , Masculino , Filogenia , Reação em Cadeia da Polimerase
17.
Virology ; 262(1): 114-28, 1999 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10489346

RESUMO

Ebola virus (Zaire subtype) is associated with high mortality disease outbreaks that commonly involve human to human transmission. Surviving patients can show evidence of prolonged virus persistence. The potential for Ebola virus to generate defective interfering (DI) particles and establish persistent infections in tissue culture was investigated. It was found that serial undiluted virus passages quickly resulted in production of an evolving population of virus minireplicons possessing both deletion and copyback type DI genome rearrangements. The tenth undiluted virus passage resulted in the establishment of virus persistently infected cell lines. Following one or two crises, these cells were stably maintained for several months with continuous shedding of infectious virus. An analysis of the estimated genome lengths of a selected set of the Ebola virus minireplicons and standard filoviruses revealed no obvious genome length rule, such as "the rule of six" found for the phylogenetically related Paramyxovirinae subfamily viruses. Minimal promoters for Ebola virus replication were found to be contained within 156 and 177 nucleotide regions of the genomic and antigenomic RNA 3' termini, respectively, based on the length of authentic termini retained in the naturally occurring minireplicons analyzed. In addition, using UV-irradiated preparations of virus released from persistently infected cells, it was demonstrated that Ebola virus DI particles could potentially be used as natural minireplicons to assay standard virus support functions.


Assuntos
Ebolavirus/patogenicidade , Doença pelo Vírus Ebola/genética , Animais , Linhagem Celular , Chlorocebus aethiops , Ebolavirus/genética , Ebolavirus/crescimento & desenvolvimento , Ebolavirus/efeitos da radiação , Humanos , Mutação/genética , Replicon/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Deleção de Sequência/genética , Raios Ultravioleta , Células Vero , Vírion/genética , Replicação Viral/genética , Replicação Viral/efeitos da radiação
18.
J Virol ; 73(7): 6024-30, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10364354

RESUMO

The activity of antibodies against filoviruses is poorly understood but has important consequences for vaccine design and passive prophylaxis. To investigate this activity, a panel of recombinant human monoclonal antibodies to Ebola virus antigens was isolated from phage display libraries constructed from RNA from donors who recovered from infection in the 1995 Ebola virus outbreak in Kikwit, Democratic Republic of Congo. Antibodies reactive with nucleoprotein (NP), envelope glycoprotein (GP), and secreted envelope glycoprotein (sGP) were characterized by immunofluorescence and radioimmunoprecipitation assays. Four antibodies reacting strongly with sGP and weakly with GP and two antibodies reacting with NP were not neutralizing. An antibody specific for GP neutralized Ebola virus to 50% at 0.4 microgram/ml as the recombinant Fab fragment and to 50% at 0.3 microgram/ml (90% at 2.6 microgram/ml) as the corresponding whole immunoglobulin G1 molecule. The studies indicate that neutralizing antibodies are produced in infection by Ebola virus although probably at a relatively low frequency. The neutralizing antibody may be useful in vaccine design and as a prophylactic agent against Ebola virus infection.


Assuntos
Anticorpos Antivirais/imunologia , Ebolavirus/imunologia , Glicoproteínas/imunologia , Doença pelo Vírus Ebola/imunologia , Proteínas do Nucleocapsídeo/imunologia , Proteínas do Envelope Viral/imunologia , Proteínas Virais , Sequência de Aminoácidos , Animais , Afinidade de Anticorpos , Antígenos Virais/imunologia , Chlorocebus aethiops , República Democrática do Congo/epidemiologia , Surtos de Doenças , Técnica Direta de Fluorescência para Anticorpo , Biblioteca Gênica , Doença pelo Vírus Ebola/sangue , Doença pelo Vírus Ebola/epidemiologia , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Dados de Sequência Molecular , Testes de Neutralização , Ensaio de Radioimunoprecipitação , Células Vero
19.
Emerg Infect Dis ; 5(1): 75-86, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10081674

RESUMO

The 1993 outbreak of hantavirus pulmonary syndrome (HPS) in the southwestern United States was associated with Sin Nombre virus, a rodent-borne hantavirus; The virus' primary reservoir is the deer mouse (Peromyscus maniculatus). Hantavirus-infected rodents were identified in various regions of North America. An extensive nucleotide sequence database of an 139 bp fragment amplified from virus M genomic segments was generated. Phylogenetic analysis confirmed that SNV-like hantaviruses are widely distributed in Peromyscus species rodents throughout North America. Classic SNV is the major cause of HPS in North America, but other Peromyscine-borne hantaviruses, e.g., New York and Monongahela viruses, are also associated with HPS cases. Although genetically diverse, SNV-like viruses have slowly coevolved with their rodent hosts. We show that the genetic relationships of hantaviruses in the Americas are complex, most likely as a result of the rapid radiation and speciation of New World sigmodontine rodents and occasional virus-host switching events.


Assuntos
Variação Genética , Síndrome Pulmonar por Hantavirus/virologia , Orthohantavírus/genética , Peromyscus/virologia , Animais , DNA Viral/análise , Reservatórios de Doenças , Orthohantavírus/isolamento & purificação , Síndrome Pulmonar por Hantavirus/transmissão , Humanos , Camundongos , América do Norte , Filogenia , Análise de Sequência de DNA
20.
J Infect Dis ; 179 Suppl 1: S28-35, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9988162

RESUMO

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. Arthralgias and myalgia were reported significantly more often by convalescents than HHCs. Evidence of Ebola virus was detected by reverse transcription-polymerase chain reaction in semen specimens up to 91 days after disease onset; however, these and all other non-blood body fluids tested negative by virus isolation. Among 81 initially antibody negative HHCs, none became antibody positive. Blood specimens of 5 HHCs not identified as EHF patients were initially antibody positive. No direct evidence of convalescent-to-HHC transmission of EHF was found, although the semen of convalescents may be infectious. The existence of initially antibody-positive HHCs suggests that mild cases of Ebola virus infection occurred and that the full extent of the EHF epidemic was probably underestimated.


Assuntos
Surtos de Doenças , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/imunologia , Adolescente , Adulto , Anticorpos Antivirais/sangue , Líquidos Corporais/virologia , Criança , Estudos de Coortes , República Democrática do Congo/epidemiologia , Ebolavirus/genética , Ebolavirus/imunologia , Ebolavirus/isolamento & purificação , Fatores Epidemiológicos , Feminino , Doença pelo Vírus Ebola/transmissão , Habitação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Viral/genética , RNA Viral/isolamento & purificação , Sêmen/virologia , Fatores de Tempo
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