Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Infect Dis ; 229(Supplement_1): S34-S39, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37578049

RESUMO

Respiratory syncytial virus (RSV) is a common pathogen causing mostly cold-like symptoms, but in very young infants and elderly individuals it can lead to severe disease and even death. There are currently promising developments both in vaccine development and in therapeutics that are expected to be approved soon. To get an impression within European countries of the laboratory diagnostics and surveillance activities, in anticipation of these developments, we queried the members of the European Respiratory Syncytial Virus Laboratory Network (RSV-LabNet, under the umbrella of the PROMISE project) via an online survey. The answers from the consortium members showed scattered monitoring and the application of a broad array of techniques in the laboratories. A majority of the members expressed strong interest in harmonization and collaboration for setting up surveillance programs and the need for sharing laboratory protocols. The additional value of RSV whole-genome sequencing is broadly appreciated, but implementation requires further development and closer collaboration. The RSV-LabNet can have an important responsibility in establishing contacts and exchange of expertise and providing a platform for communication to advance diagnostics, preparedness, and surveillance.


Assuntos
Laboratórios , Vírus Sincicial Respiratório Humano , Idoso , Lactente , Humanos , Vírus Sincicial Respiratório Humano/genética , Europa (Continente)/epidemiologia , Sequenciamento Completo do Genoma
2.
J Infect Dis ; 229(Supplement_1): S84-S91, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37930815

RESUMO

Several immunization products are currently being developed against respiratory syncytial virus (RSV) for children, pregnant females, and older adults, and some products have already received authorization. Therefore, studies to monitor the effectiveness of these products are needed in the following years. To assist researchers to conduct postmarketing studies, we developed a generic protocol for register-based cohort studies to evaluate immunization product effectiveness against RSV-specific and nonspecific outcomes. To conduct a study on the basis of this generic protocol, the researchers can use any relevant databases or healthcare registers that are available at the study site.


Assuntos
Vírus Sincicial Respiratório Humano , Vacinas , Criança , Feminino , Gravidez , Humanos , Idoso , Anticorpos Monoclonais/uso terapêutico , Estudos de Coortes , Vacinação , Medicamentos Genéricos
3.
J Infect Dis ; 229(Supplement_1): S92-S99, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37935046

RESUMO

Monitoring the real-life effectiveness of respiratory syncytial virus (RSV) products is of major public health importance. This generic protocol for a test-negative design study aims to address currently envisioned approaches for RSV prevention (monoclonal antibodies and vaccines) to study effectiveness of these products among target groups: children, older adults, and pregnant women. The generic protocol approach was chosen to allow for flexibility in adapting the protocol to a specific setting. This protocol includes severe acute respiratory infection (SARI) and acute respiratory infection (ARI), both due to RSV, as end points. These end points can be applied to studies in hospitals, primarily targeting patients with more severe disease, but also to studies in general practitioner clinics targeting ARI.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Infecções Respiratórias , Gravidez , Criança , Humanos , Feminino , Idoso , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Estudos de Casos e Controles , Vacinação , Imunização , Medicamentos Genéricos
5.
J Infect Dis ; 214(suppl 3): S258-S262, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27587631

RESUMO

During the Ebola virus outbreak of 2013-2016, the Viral Special Pathogens Branch field laboratory in Sierra Leone tested approximately 26 000 specimens between August 2014 and October 2015. Analysis of the B2M endogenous control Ct values showed its utility in monitoring specimen quality, comparing results with different specimen types, and interpretation of results. For live patients, blood is the most sensitive specimen type and oral swabs have little diagnostic utility. However, swabs are highly sensitive for diagnostic testing of corpses.


Assuntos
Surtos de Doenças , Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/diagnóstico , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Serviços de Laboratório Clínico , Ebolavirus/genética , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/virologia , Humanos , Laboratórios , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Serra Leoa/epidemiologia
6.
Zoonoses Public Health ; 71(3): 274-280, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38110840

RESUMO

BACKGROUND AND OBJECTIVE: No autochthonous human cases of Japanese encephalitis (JE) have been reported to date in the European Union (EU). In this study, we assess the likelihood of Japanese encephalitis virus (JEV) introduction and transmission within the EU and propose outbreak response measures. RISK ASSESSMENT: Given the global geographical distribution of JEV, the probability of virus introduction into the EU is currently very low, with viremic bird migration being the most plausible pathway of introduction. However, this likelihood would significantly increase if the virus were to become established in the Middle East, Caucasus, Central Asia or Africa. Considering the environmental conditions that are expected to be conducive for virus circulation, there is a high likelihood of virus transmission within the EU after its introduction in environmentally suitable areas. The spread of the virus within the EU would likely occur through the movement of wild birds, pigs and mosquitoes. MITIGATION: To mitigate or potentially contain the emergence of JE in the EU, early detection of both human and animal cases will be crucial.


Assuntos
Culicidae , Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Doenças dos Suínos , Animais , Humanos , Suínos , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/veterinária , União Europeia , Aves
7.
Sci Rep ; 14(1): 1378, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38228693

RESUMO

A two-step strategy combining assisted benchmark testing (entry controls) and External Quality Assessments (EQAs) with blinded simulated clinical specimens to enhance and maintain the quality of nucleic acid amplification testing was developed. This strategy was successfully applied to 71 diagnostic laboratories in The Netherlands when upscaling the national diagnostic capacity during the SARS-CoV-2 pandemic. The availability of benchmark testing in combination with advice for improvement substantially enhanced the quality of the laboratory testing procedures for SARS-CoV-2 detection. The three subsequent EQA rounds demonstrated high quality testing with regard to specificity (99.6% correctly identified) and sensitivity (93.3% correctly identified). Even with the implementation of novel assays, changing workflows using diverse equipment and a high degree of assay heterogeneity, the overall high quality was maintained using this two-step strategy. We show that in contrast to the limited value of Cq value for absolute proxies of viral load, these Cq values can, in combination with metadata on strategies and techniques, provide valuable information for laboratories to improve their procedures. In conclusion, our two-step strategy (preparation phase followed by a series of EQAs) is a rapid and flexible system capable of scaling, improving, and maintaining high quality diagnostics even in a rapidly evolving (e.g. pandemic) situation.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiologia , Laboratórios , Técnicas de Laboratório Clínico/métodos , Teste para COVID-19 , Benchmarking , Patologia Molecular , Sensibilidade e Especificidade
8.
J Gen Virol ; 93(Pt 2): 235-246, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21994322

RESUMO

Interleukin-1ß (IL-1ß) is a potent pro-inflammatory cytokine involved in the pathogenesis of HCV, but the sensors and underlying mechanisms that facilitate HCV-induced IL-1ß proteolytic activation and secretion remains unclear. In this study, we have identified a signalling pathway leading to IL-1ß activation and secretion in response to HCV infection. Previous studies have shown the induction and secretion of IL-1ß through the inflammasome complex in macrophages/monocytes. Here, we report for the first time the induction and assembly of the NALP3-inflammasome complex in human hepatoma cells infected with HCV (JFH-1). We demonstrate that activation of IL-1ß in HCV-infected cells involves the proteolytic processing of pro-caspase-1 into mature caspase-1 in a multiprotein inflammasome complex. Next, we demonstrate that HCV is sensed by NALP3 protein, which recruits the adaptor protein ASC for the assembly of the inflammasome complex. Using a small interfering RNA approach, we further show that components of the inflammasome complex are involved in the activation of IL-1ß in HCV-infected cells. Our study also demonstrates the role of reactive oxygen species in HCV-induced IL-1ß secretion. Collectively, these observations provide an insight into the mechanism of IL-1ß processing and secretion, which is likely to provide novel strategies for targeting the viral or cellular determinants to arrest the progression of liver disease associated with chronic HCV infection.


Assuntos
Caspase 1/metabolismo , Hepacivirus/imunologia , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Proteínas Adaptadoras de Sinalização CARD , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Proteínas do Citoesqueleto/metabolismo , Hepatócitos/imunologia , Hepatócitos/virologia , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Multimerização Proteica , Transdução de Sinais
9.
Antiviral Res ; 200: 105281, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35292289

RESUMO

Global analysis of the susceptibility of influenza viruses to neuraminidase (NA) inhibitors (NAIs) and the polymerase acidic (PA) inhibitor (PAI) baloxavir was conducted by five World Health Organization Collaborating Centres for Reference and Research on Influenza during two periods (May 2018-May 2019 and May 2019-May 2020). Combined phenotypic and NA sequence-based analysis revealed that the global frequency of viruses displaying reduced or highly reduced inhibition (RI or HRI) or potential to show RI/HRI by NAIs remained low, 0.5% (165/35045) and 0.6% (159/26010) for the 2018-2019 and 2019-2020 periods, respectively. The most common amino acid substitution was NA-H275Y (N1 numbering) conferring HRI by oseltamivir and peramivir in A(H1N1)pdm09 viruses. Combined phenotypic and PA sequence-based analysis showed that the global frequency of viruses showing reduced susceptibility to baloxavir or carrying substitutions associated with reduced susceptibility was low, 0.5% (72/15906) and 0.1% (18/15692) for the 2018-2019 and 2019-2020 periods, respectively. Most (n = 61) of these viruses had I38→T/F/M/S/L/V PA amino acid substitutions. In Japan, where baloxavir use was highest, the rate was 4.5% (41/919) in the 2018-2019 period and most of the viruses (n = 32) had PA-I38T. Zoonotic viruses isolated from humans (n = 32) in different countries did not contain substitutions in NA associated with NAI RI/HRI phenotypes. One A(H5N6) virus had a dual substitution PA-I38V + PA-E199G, which may reduce susceptibility to baloxavir. Therefore, NAIs and baloxavir remain appropriate choices for the treatment of influenza virus infections, but close monitoring of antiviral susceptibility is warranted.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Substituição de Aminoácidos , Antivirais/farmacologia , Antivirais/uso terapêutico , Dibenzotiepinas , Farmacorresistência Viral/genética , Endonucleases/genética , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza B , Morfolinas , Neuraminidase/genética , Neuraminidase/uso terapêutico , Oseltamivir/farmacologia , Oseltamivir/uso terapêutico , Piridonas , Triazinas
10.
Front Public Health ; 9: 659504, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178918

RESUMO

Background: The 2014-2016 West Africa Ebola virus disease outbreak heavily impacted the Republics of Guinea, Sierra Leone, and Liberia. The outbreak uncovered the weaknesses of the public health systems, including inadequately trained and insufficient health personnel as well as limited and poorly equipped health infrastructures. These weaknesses represent significant threats to global health security. In the wake of the outbreak, affected countries made urgent requests for international engagement to help strengthening the public health systems. Methods: This work describes the successful multi-year implementation of a laboratory capacity building program in the Republic of Guinea. The program integrated biorisk and quality management systems training, infectious diseases diagnostic training, facility engineering and maintenance training, and mentorship to strengthen Guinea's bio-surveillance capacity. Results: The major outcome of these efforts was an established and local staff-operated public health laboratory that performs disease surveillance and reporting and diagnostic of priority diseases and pathogens of security concerns. Conclusions: This work has improved the Guinea country's capabilities to address country public health issues and preparedness to respond to future infectious disease threats.


Assuntos
Doença pelo Vírus Ebola , Fortalecimento Institucional , Surtos de Doenças/prevenção & controle , Guiné/epidemiologia , Doença pelo Vírus Ebola/diagnóstico , Humanos , Laboratórios , Libéria , Serra Leoa
11.
Ann Epidemiol ; 60: 35-44, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33965545

RESUMO

PURPOSE: During the 2014-2016 Ebola outbreak in West Africa, the Sierra Leone Ministry of Health and Sanitation (MoHS), the US Centers for Disease Control and Prevention, and responding partners under the coordination of the National Ebola Response Center (NERC) and the MoHS's Emergency Operation Center (EOC) systematically recorded information from the 117 Call Center system and district alert phone lines, case investigations, laboratory sample testing, clinical management, and safe and dignified burial records. Since 2017, CDC assisted MoHS in building and managing the Sierra Leone Ebola Database (SLED) to consolidate these major data sources. The primary objectives of the project were helping families to identify the location of graves of their loved ones who died at the time of the Ebola epidemic through the SLED Family Reunification Program and creating a data source for epidemiological research. The objective of this paper is to describe the process of consolidating epidemic records into a useful and accessible data collection and to summarize data characteristics, strength, and limitations of this unique information source for public health research. METHODS: Because of the unprecedented conditions during the epidemic, most of the records collected from responding organizations required extensive processing before they could be used as a data source for research or the humanitarian purpose of locating burial sites. This process required understanding how the data were collected and used during the outbreak. To manage the complexity of processing the data obtained from various sources, the Sierra Leone Ebola Database (SLED) Team used an organizational strategy that allowed tracking of the data provenance and lifecycle. RESULTS: The SLED project brought raw data into one consolidated data collection. It provides researchers with secure and ethical access to the SLED data and serves as a basis for the research capacity building in Sierra Leone. The SLED Family Reunification Program allowed Sierra Leonean families to identify location of the graves of loved ones who died during the Ebola epidemic. CONCLUSIONS: The SLED project consolidated and utilized epidemic data recorded during the Sierra Leone Ebola Virus Disease outbreak that were collected and contributed to SLED by national and international organizations. This project has provided a foundation for developing a method of ethical and secure SLED data access while preserving the host nation's data ownership. SLED serves as a data source for the SLED Family Reunification Program and for epidemiological research. It presents an opportunity for building research capacity in Sierra Leone and provides a foundation for developing a relational database. Large outbreak data systems such as SLED provide a unique opportunity for researchers to improve responses to epidemics and indicate the need to include data management preparedness in the plans for emergency response.


Assuntos
Epidemias , Doença pelo Vírus Ebola , Gerenciamento de Dados , Surtos de Doenças , Doença pelo Vírus Ebola/epidemiologia , Humanos , Serra Leoa/epidemiologia
12.
Afr J Lab Med ; 10(1): 1414, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858796

RESUMO

BACKGROUND: Ebola virus emerged in West Africa in December 2013. The ease of mobility, porous borders, and lack of public health infrastructure led to the largest Ebola virus disease (EVD) outbreak to date. INTERVENTION: The 2013 EVD outbreak signalled the need for laboratory diagnostic capabilities in areas without strong public health systems. As part of the United States' Department of Defense response, MRIGlobal was contracted to design, fabricate, equip, deploy, and operate two mobile diagnostic laboratories (MDLs). The first laboratory analysed blood samples from patients in an adjacent Ebola Treatment Centre (ETC) and buccal swabs from the deceased in the community in Moyamba, Sierra Leone. The second laboratory was deployed to support an ETC in Conakry, Guinea. The Department of Defense provided real-time quantitative reverse transcription polymerase chain reaction assays that were deployed and validated on-site. LESSONS LEARNT: Prompt and accurate molecular diagnostics reduced sample turn-around times from over 24 h to under 4 h. Experienced laboratory staff tested up to 110 samples per day and on-site engineering proved necessary for MDL setup and operation. As the Ebola response slowed, the sustainment of the MDLs' operations was prioritised, including staff training and the transition of the MDLs to local governments. Training programmes for local staff were prepared in Sierra Leone and Guinea. RECOMMENDATIONS: The MRIGlobal MDL team significantly contributed to establishing increased laboratory capacity during the EVD outbreak in West Africa. Using the MDLs for molecular diagnosis is highly recommended until more sustainable solutions can be provided.

14.
Open Forum Infect Dis ; 2(4): ofv164, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26716104

RESUMO

Background. In August 2012, the Chicago Department of Public Health (CDPH) was notified of acute respiratory illness, including 1 fatality, among a group of meeting attendees who stayed at a Chicago hotel during July 30-August 3, 2012. Suspecting Legionnaires' disease (LD), CDPH advised the hotel to close their swimming pool, spa, and decorative lobby fountain and began an investigation. Methods. Case finding included notification of individuals potentially exposed during July 16-August 15, 2012. Individuals were interviewed using a standardized questionnaire. An environmental assessment was performed. Results. One hundred fourteen cases were identified: 11 confirmed LD, 29 suspect LD, and 74 Pontiac fever cases. Illness onsets occurred July 21-August 22, 2012. Median age was 48 years (range, 22-82 years), 64% were male, 59% sought medical care (15 hospitalizations), and 3 died. Relative risks for hotel exposures revealed that persons who spent time near the decorative fountain or bar, both located in the lobby were respectively 2.13 (95%, 1.64-2.77) and 1.25 (95% CI, 1.09-1.44) times more likely to become ill than those who did not. Legionella pneumophila serogroup 1 was isolated from samples collected from the fountain, spa, and women's locker room fixtures. Legionella pneumophila serogroup 1 environmental isolates and a clinical isolate had matching sequence-based types. Hotel maintenance records lacked a record of regular cleaning and disinfection of the fountain. Conclusions. Environmental testing identified Legionella in the hotel's potable water system. Epidemiologic and laboratory data indicated the decorative fountain as the source. Poor fountain maintenance likely created favorable conditions for Legionella overgrowth.

15.
PLoS One ; 8(2): e56367, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23437118

RESUMO

Our previous studies have shown the induction and maturation of transforming growth factor-beta 1 (TGF-ß1) in HCV-infected human hepatoma cells. In this study, we have investigated the molecular mechanism of TGF-ß1 gene expression in response to HCV infection. We demonstrate that HCV-induced transcription factors AP-1, Sp1, NF-κB and STAT-3 are involved in TGF-ß1 gene expression. Using chromatin immunoprecipitation (ChIP) assay, we further show that AP-1 and Sp1 interact with TGF-b1 promoter in vivo in HCV-infected cells. In addition, we demonstrate that HCV-induced TGF-ß1 gene expression is mediated by the activation of cellular kinases such as p38 MAPK, Src, JNK, and MEK1/2. Next, we determined the role of secreted bioactive TGF-ß1 in human hepatic stellate cells (HSCs) activation and invasion. Using siRNA approach, we show that HCV-induced bioactive TGF-ß1 is critical for the induction of alpha smooth muscle actin (α-SMA) and type 1 collagen, the markers of HSCs activation and proliferation. We further demonstrate the potential role of HCV-induced bioactive TGF-ß1 in HSCs invasion/cell migration using a transwell Boyden chamber. Our results also suggest the role of HCV-induced TGF-ß1 in HCV replication and release. Collectively, these observations provide insight into the mechanism of TGF-ß1 promoter activation, as well as HSCs activation and invasion, which likely manifests in liver fibrosis associated with HCV infection.


Assuntos
Hepacivirus/fisiologia , Células Estreladas do Fígado/patologia , Células Estreladas do Fígado/virologia , Regiões Promotoras Genéticas/genética , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição AP-1/metabolismo , Fator de Crescimento Transformador beta1/genética , Animais , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Linhagem Celular Tumoral , Análise Mutacional de DNA , Furina/metabolismo , Regulação da Expressão Gênica , Genes Reporter , Células Estreladas do Fígado/metabolismo , Humanos , Luciferases/metabolismo , Vison , Dados de Sequência Molecular , Transdução de Sinais/genética , Ativação Transcricional/genética , Fator de Crescimento Transformador beta1/metabolismo , Replicação Viral
16.
Virology ; 412(2): 284-96, 2011 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-21296375

RESUMO

In this study, we demonstrated the molecular mechanisms of TGF-ß1 induction as well as proteolytic activation in HCV (JFH-1)-infected cells. Our studies showed the synthesis and secretion of TGF-ß1 in HCV-infected cells which was reduced in the presence of Ca(2+) chelators, an inhibitor of mitochondrial Ca(2+) uptake, and antioxidants. We also showed that the expression of HCV NS proteins NS3/4A, and NS5A can induce TGF-ß1 by cell-based luciferase assay. Furthermore, mutational analysis revealed that the functionally active protease domain of NS3 and N-terminus domain of NS5A are required for TGF-ß1 activity. Using siRNA approach we demonstrated that HCV-induced furin and thrombospondin-1 (TSP-1) are involved in the proteolytic activation of TGF-ß1. Our results also suggest that TGF-ß1 positively regulates HCV RNA replication. Collectively, these observations provide insight into the mechanism of TGF-ß1 activation, which likely manifest in liver fibrosis associated with hepatitis C infection.


Assuntos
Furina/metabolismo , Hepacivirus/fisiologia , Interações Hospedeiro-Patógeno , Trombospondina 1/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Replicação Viral , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular , Análise Mutacional de DNA , Furina/antagonistas & inibidores , Inativação Gênica , Genes Reporter , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Luciferases/genética , Luciferases/metabolismo , Mutagênese Sítio-Dirigida , Trombospondina 1/antagonistas & inibidores , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA