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1.
PLoS Pathog ; 15(9): e1008050, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31557262

RESUMO

Crimean-Congo hemorrhagic fever (CCHF) is the most medically important tick-borne viral disease of humans and tuberculosis is the leading cause of death worldwide by a bacterial pathogen. These two diseases overlap geographically, however, concurrent infection of CCHF virus (CCHFV) with mycobacterial infection has not been assessed nor has the ability of virus to persist and cause long-term sequela in a primate model. In this study, we compared the disease progression of two diverse strains of CCHFV in the recently described cynomolgus macaque model. All animals demonstrated signs of clinical illness, viremia, significant changes in clinical chemistry and hematology values, and serum cytokine profiles consistent with CCHF in humans. The European and Asian CCHFV strains caused very similar disease profiles in monkeys, which demonstrates that medical countermeasures can be evaluated in this animal model against multiple CCHFV strains. We identified evidence of CCHFV persistence in the testes of three male monkeys that survived infection. Furthermore, the histopathology unexpectedly revealed that six additional animals had evidence of a latent mycobacterial infection with granulomatous lesions. Interestingly, CCHFV persisted within the granulomas of two animals. This study is the first to demonstrate the persistence of CCHFV in the testes and within the granulomas of non-human primates with concurrent latent tuberculosis. Our results have important public health implications in overlapping endemic regions for these emerging pathogens.

2.
Sci Adv ; 5(7): eaaw9535, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31309159

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) is an important human pathogen. Limited evidence suggests that antibodies can protect humans against lethal CCHFV disease but the protective efficacy of antibodies has never been evaluated in adult animal models. Here, we used adult mice to investigate the protection provided against CCHFV infection by glycoprotein-targeting neutralizing and non-neutralizing monoclonal antibodies (mAbs). We identified a single non-neutralizing antibody (mAb-13G8) that protected adult type I interferon-deficient mice >90% when treatment was initiated before virus exposure and >60% when administered after virus exposure. Neutralizing antibodies known to protect neonatal mice from lethal CCHFV infection failed to confer protection regardless of immunoglobulin G subclass. The target of mAb-13G8 was identified as GP38, one of multiple proteolytically cleaved glycoproteins derived from the CCHFV glycoprotein precursor polyprotein. This study reveals GP38 as an important antibody target for limiting CCHFV pathogenesis and lays the foundation to develop immunotherapeutics against CCHFV in humans.

3.
J Virol Methods ; 270: 12-17, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30998959

RESUMO

There is a pressing need for sustainable and sensitive immunodiagnostics for use in public health efforts to understand and combat the threat of endemic and emerging infectious diseases. In this proof-of-concept work, we describe an immunodiagnostic approach based on the utilization of virus-like particles (VLPs) in a magnetic bead-based platform for multiplexed detection of antiviral humoral response. A retroviral-based VLP, that presents Venezuelan equine encephalitis virus E1/E2 glycoprotein antigen on its surface, was synthesized and coupled to magnetic beads to create VLP-conjugated microspheres (VCMs). Using these VCMs, IgM and IgG antibodies were detectable in nonhuman primate (NHP) and human clinical serum samples at dilutions of 1 × 10 Basile et al. [4] and greater. We also extended the VCM methodology to an Old World alphavirus, chikungunya virus, demonstrating the flexibility of this approach toward different VLP architectures. When multiplexed on the MAGPIX® platform, this method provided differential detection between Old World and New World alphaviral IgM. This flexible, immunodiagnostic method, based on the MAGPIX® platform, demonstrates compatibility of particulate antigens with bead-based assays, improves sensitivity by up to 2-logs, and has faster sample-to-answer time over traditional methods.

4.
PLoS Negl Trop Dis ; 11(1): e0005254, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28081120

RESUMO

BACKGROUND: During Dec-2013, a chikungunya virus (CHIKV) outbreak was first detected in the French-West Indies. Subsequently, the virus dispersed to other Caribbean islands, continental America and many islands in the Pacific Ocean. Previous estimates of the attack rate were based on declaration of clinically suspected cases. METHODS/PRINCIPAL FINDINGS: Individual testing for CHIKV RNA of all (n = 16,386) blood donations between Feb-24th 2014 and Jan-31st 2015 identified 0·36% and 0·42% of positives in Guadeloupe and Martinique, respectively. The incidence curves faithfully correlated with those of suspected clinical cases in the general population of Guadeloupe (abrupt epidemic peak), but not in Martinique (flatter epidemic growth). No significant relationship was identified between CHIKV RNA detection and age-classes or blood groups. Prospective (Feb-2014 to Jan-2015; n = 9,506) and retrospective (Aug-2013 to Feb-2014; n = 6,559) seroepidemiological surveys in blood donors identified a final seroprevalence of 48·1% in Guadeloupe and 41·9% in Martinique. Retrospective survey also suggested the absence or limited "silent" CHIKV circulation before the outbreak. Parameters associated with increased seroprevalence were: Gender (M>F), KEL-1, [RH+1/KEL-1], [A/RH+1] and [A/RH+1/KEL-1] blood groups in Martiniquan donors. A simulation model based on observed incidence and actual seroprevalence values predicted 2·5 and 2·3 days of asymptomatic viraemia in Martiniquan and Guadeloupian blood donors respectively. CONCLUSIONS/SIGNIFICANCE: This study, implemented promptly with relatively limited logistical requirements during CHIKV emergence in the Caribbean, provided unique information regarding retrospective and prospective epidemiology, infection risk factors and natural history of the disease. In the stressful context of emerging infectious disease outbreaks, blood donor-based studies can serve as robust and cost-effective first-line tools for public health surveys.


Assuntos
Sangue/virologia , Febre de Chikungunya/sangue , Vírus Chikungunya/isolamento & purificação , Adulto , Idoso , Anticorpos Antivirais/sangue , Doadores de Sangue/estatística & dados numéricos , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Feminino , Guadalupe/epidemiologia , Humanos , Masculino , Martinica/epidemiologia , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Estudos Soroepidemiológicos , Voluntários , Adulto Jovem
5.
Am J Infect Control ; 44(12): 1687-1688, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27575772

RESUMO

In 2015, the French Armed Forces deployed a biosafety level 3 (BSL3) field laboratory as a part of an Ebola treatment center in Guinea. When closing the center, laboratory decontamination operations were necessary. We present the decontamination protocols applied for the BSL3 field laboratory, making the entire module ready for a future use.


Assuntos
Descontaminação/métodos , Equipamentos Médicos Duráveis , Doença pelo Vírus Ebola/diagnóstico , Laboratórios , França , Guiné , Humanos , Instalações Militares
6.
Euro Surveill ; 21(28)2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27447300

RESUMO

Following of the emergence of Zika virus in Brazil in 2015, an epidemiological surveillance system was quickly implemented in the French overseas Territories of America (FTA) according to previous experience with dengue and chikungunya and has detected first cases of Zika. General practitioners and medical microbiologists were invited to report all clinically suspected cases of Zika, laboratory investigations were systematically conducted (RT-PCR). On 18 December, the first autochthonous case of Zika virus infection was confirmed by RT-PCR on French Guiana and Martinique, indicating introduction of Zika virus in FTA. The viral circulation of Zika virus was then also confirmed on Guadeloupe and Saint-Martin. We report here early findings on 203 confirmed cases of Zika virus infection identified by RT-PCR or seroneutralisation on Martinique Island between 24 November 2015 and 20 January 2016. All cases were investigated. Common clinical signs were observed (maculopapular rash, arthralgia, fever, myalgia and conjunctival hyperaemia) among these patients, but the rash, the foundation of our case definition, may be absent in a significant proportion of patients (16%). These results are important for the implementation of a suspected case definition, the main tool for epidemiological surveillance, in territories that may be affected by ZIKV emergence, including Europe.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Surtos de Doenças , Vigilância da População , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia , Zika virus/isolamento & purificação , Humanos , Martinica/epidemiologia , RNA Viral/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Zika virus/genética , Infecção por Zika virus/transmissão
7.
Euro Surveill ; 21(6)2016.
Artigo em Inglês | MEDLINE | ID: mdl-26898198

RESUMO

We report three unrelated cases of Zika virus infection in patients returning from Martinique, Brazil and Colombia respectively, to Montpellier, France. They developed symptoms compatible with a mosquito-borne disease, and serological and molecular investigations indicated a recent Zika virus infection. Considering the recent warning for the likely teratogenicity of Zika virus and the presence of competent mosquito vectors in southern France, these cases highlight the need for awareness of physicians and laboratories in Europe.


Assuntos
Imunoglobulina G/sangue , Imunoglobulina M/sangue , Viagem , Infecção por Zika virus/diagnóstico , Zika virus/isolamento & purificação , Aedes/virologia , Animais , Anticorpos Antivirais/sangue , Brasil , Região do Caribe , Colômbia , Surtos de Doenças , Exantema/virologia , Feminino , Febre/etiologia , Febre/virologia , França , Humanos , Insetos Vetores/virologia , Masculino , Martinica , Pessoa de Meia-Idade , RNA Viral/sangue , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem , Zika virus/genética , Zika virus/imunologia , Infecção por Zika virus/sangue , Infecção por Zika virus/virologia
9.
J Clin Virol ; 71: 89-92, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26339948

RESUMO

BACKGROUND: The recent emergence of Chikungunya Virus (CHIKV) in the Americas constitutes a major public health problem on this continent, where the mosquito vector is widespread. The rapid diagnosis of suspected cases is essential for the monitoring and control of this ongoing outbreak. However, this requires reliable tools that are difficult to establish in areas without specialized laboratories. OBJECTIVES: The aim was to evaluate the performances of serum samples spotted onto filter paper for molecular and serological diagnosis of Chikungunya infection. STUDY DESIGN: Analyses were performed from frozen sera and serum spotted onto filter paper provided from 121 Chikungunya suspected cases collected at a biological laboratory on Saint-Martin Island. RESULTS: This approach performed well in comparisons with standard methods, with a sensitivity of 100% and a specificity of 93.6% for the combined technical approaches (RT-PCR and serological results). Comparisons of serum samples spotted onto filter paper and frozen samples showed a concordance rate of 94.8% in molecular tests and 98.2% in serological tests. CONCLUSIONS: This simple sampling technique could overcome the problems of the lack of efficient CHIKV diagnosis tools in remote regions, providing good results regardless of the molecular or serological approach used. This simple filter paper-based method can be used to diagnose both chikungunya and dengue infections, as previously demonstrated following transport at ambient temperature to specialized laboratories. Given the set-up costs and high performance of this method, it could be recommended for the monitoring and control of Chikungunya virus expansion in the Americas and in other affected regions.


Assuntos
Febre de Chikungunya/diagnóstico , Dessecação , Soro/virologia , Manejo de Espécimes/métodos , Américas , Humanos , Técnicas de Diagnóstico Molecular/métodos , Papel , Sensibilidade e Especificidade , Testes Sorológicos/métodos
10.
Emerg Infect Dis ; 20(12): 2129-32, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25418184

RESUMO

Chikungunya virus (CHIKV) is present or emerging in dengue virus-endemic areas. Infections caused by these viruses share some common signs/symptoms, but prognosis, patient care, and persistent symptoms differ. Thus, accurate diagnostic methods are essential for differentiating the infections. We evaluated 4 CHIKV serologic diagnostic tests, 2 of which showed poor sensitivity and specificity.


Assuntos
Febre de Chikungunya/diagnóstico , Vírus Chikungunya/classificação , Kit de Reagentes para Diagnóstico , Testes Sorológicos/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Humanos , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Testes Sorológicos/normas
11.
Emerg Infect Dis ; 19(12): 1996-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24274113

RESUMO

We investigated 4 related human cases of cowpox virus infection reported in France during 2011. Three patients were infected by the same strain, probably transmitted by imported pet rats, and the fourth patient was infected by another strain. The 2 strains were genetically related to viruses previously isolated from humans with cowpox infection in Europe.


Assuntos
Vírus da Varíola Bovina/classificação , Vírus da Varíola Bovina/genética , Varíola Bovina/epidemiologia , Adulto , Animais , Linhagem Celular , Criança , Varíola Bovina/transmissão , Vírus da Varíola Bovina/isolamento & purificação , Feminino , França/epidemiologia , Genoma Viral , Humanos , Masculino , Dados de Sequência Molecular , Filogenia , Ratos
12.
J Virol Methods ; 186(1-2): 176-83, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22981457

RESUMO

Quantitation of intracellular viral genomes is critical in both clinical and fundamental virology. Quantitative real time PCR (qPCR) is currently the gold standard to detect and monitor virus infections, due to its high sensitivity and reproducibility. The reliability of qPCR data depends primarily on the technical process. Normalization, which corrects inter-sample variations related to both pre-analytical and qPCR steps, is a key point of an accurate quantitation. Total DNA input and qPCR-measured standards were evaluated to normalize intracellular Vaccinia virus (VACV) genomes. Three qPCR assays targeting either a single-copy chromosomic gene, a repeated chromosomic DNA sequence, or a mitochondrial DNA sequence were compared. qPCR-measured standards, unlike total DNA input, allowed for accurate normalization of VACV genome, regardless of the cell number. Among PCR-measured standards, chromosomic DNA and mitochondrial DNA were equivalent to normalize VACV DNA and multi-copy standards displayed lower limits of quantitation than single-copy standards. The combination of two qPCR-measured standards slightly improved the reliability of the normalization. Using one or two multi-copy standards must be favored for relative quantitation of intracellular VACV DNA. This concept could be applied to other DNA viruses.


Assuntos
DNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Carga Viral/métodos , Animais , Humanos , Reação em Cadeia da Polimerase em Tempo Real/normas , Vírus Vaccinia/isolamento & purificação , Carga Viral/normas
13.
Antiviral Res ; 96(2): 187-95, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22884885

RESUMO

Genetic and biochemical data have identified at least four viral proteins essential for vaccinia virus (VACV) DNA synthesis: the DNA polymerase E9, its processivity factor (the heterodimer A20/D4) and the primase/helicase D5. These proteins are part of the VACV replication complex in which A20 is a central subunit interacting with E9, D4 and D5. We hypothesised that molecules able to modulate protein-protein interactions within the replication complex may represent a new class of compounds with anti-orthopoxvirus activities. In this study, we adapted a forward duplex yeast two-hybrid assay to screen more than 27,000 molecules in order to identify inhibitors of A20/D4 and/or A20/D5 interactions. We identified two molecules that specifically inhibited both interactions in yeast. Interestingly, we observed that these compounds displayed a similar antiviral activity to cidofovir (CDV) against VACV in cell culture. We further showed that these molecules were able to inhibit the replication of another orthopoxvirus (i.e. cowpox virus), but not the herpes simplex virus type 1 (HSV-1), an unrelated DNA virus. We also demonstrated that the antiviral activity of both compounds correlated with an inhibition of VACV DNA synthesis. Hence, these molecules may represent a starting point for the development of new anti-orthopoxvirus drugs.


Assuntos
Antivirais/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos/métodos , Vírus Vaccinia/efeitos dos fármacos , Proteínas Virais/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/farmacologia , Linhagem Celular , Vírus da Varíola Bovina/efeitos dos fármacos , Humanos , Ligação Proteica/efeitos dos fármacos , Técnicas do Sistema de Duplo-Híbrido , Leveduras/genética
14.
Case Rep Dermatol ; 3(3): 186-94, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22110431

RESUMO

The case presented here points towards the fact that skin lesion observed with a cowpox virus is a rare event but should be considered more as the number of cases has increased in the last years. Cowpox virus (CPXV) belongs to the Poxviridae family. The transmission of CPXV to humans is caused by wild rodents or mostly by domestic animals and pet rats. In humans, CPXV is responsible for localized skin lesions regularly accompanied by lymphadenopathy. The lesions remain localized but self-inoculation from the primary lesions could occur. Then physicians have to be vigilant concerning bandages. In this case report, a necrotic and ulcerated lesion of a CPXV infection in a young boy is reported. The CPXV was possibly transmitted by wild rodents. The importance of performing the diagnosis is also pointed out. Virus information was obtained from phylogenetic analyses showing that the CPXV isolate was distinct from outbreaks of human cowpox which occurred in 2009 in France and Germany but was close to the CPXV Brighton Red strain. For several years, cases of viral zoonosis caused by CPXV have increased and physicians should be made aware that people could be infected without history of direct contact with animals.

15.
J Infect ; 63(5): 391-3, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21723880
16.
Virol J ; 8: 249, 2011 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-21600011

RESUMO

BACKGROUND: The genus Nairovirus in the family Bunyaviridae contains 34 tick-borne viruses classified into seven serogroups. Hazara virus (HAZV) belongs to the Crimean-Congo hemorrhagic fever (CCHF) serogroup that also includes CCHF virus (CCHFV) a major pathogen for humans. HAZV is an interesting model to study CCHFV due to a close serological and phylogenetical relationship and a classification which allows handling in a BSL2 laboratory. Nairoviruses are characterized by a tripartite negative-sense single stranded RNA genome (named L, M and S segments) that encode the RNA polymerase, the Gn-Gc glycoproteins and the nucleoprotein (NP), respectively. Currently, there are neither vaccines nor effective therapies for the treatment of any bunyavirus infection in humans. In this study we report, for the first time, the use of RNA interference (RNAi) as an approach to inhibit nairovirus replication. RESULTS: Chemically synthesized siRNAs were designed to target the mRNA produced by the three genomic segments. We first demonstrated that the siRNAs targeting the NP mRNA displayed a stronger antiviral effect than those complementary to the L and M transcripts in A549 cells. We further characterized the two most efficient siRNAs showing, that the induced inhibition is specific and associated with a decrease in NP synthesis during HAZV infection. Furthermore, both siRNAs depicted an antiviral activity when used before and after HAZV infection. We next showed that HAZV was sensitive to ribavirin which is also known to inhibit CCHFV. Finally, we demonstrated the additive or synergistic antiviral effect of siRNAs used in combination with ribavirin. CONCLUSIONS: Our study highlights the interest of using RNAi (alone or in combination with ribavirin) to treat nairovirus infection. This approach has to be considered for the development of future antiviral compounds targeting CCHFV, the most pathogenic nairovirus.


Assuntos
Antivirais/farmacologia , Produtos Biológicos/farmacologia , Nairovirus/efeitos dos fármacos , Nairovirus/fisiologia , RNA Interferente Pequeno/farmacologia , Ribavirina/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Linhagem Celular , Cercopithecus aethiops , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana
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