304 results match your criteria ebov challenge


The impact of malaria coinfection on Ebola virus disease outcomes: A systematic review and meta-analysis.

PLoS One 2021 24;16(5):e0251101. Epub 2021 May 24.

Malaria Consortium, London, United Kingdom.

Introduction: Viral outbreaks present a particular challenge in countries in Africa where there is already a high incidence of other infectious diseases, including malaria which can alter immune responses to secondary infection. Ebola virus disease (EVD) is one such problem; understanding how Plasmodium spp. and Ebolavirus (EBOV) interact is important for future outbreaks. Read More

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Identification of Novel Antiviral Compounds Targeting Entry of Hantaviruses.

Viruses 2021 04 16;13(4). Epub 2021 Apr 16.

Institute of Microbiology, University Hospital Center and University of Lausanne, Rue du Bugnon 48, CH-1011 Lausanne, Switzerland.

Hemorrhagic fever viruses, among them orthohantaviruses, arenaviruses and filoviruses, are responsible for some of the most severe human diseases and represent a serious challenge for public health. The current limited therapeutic options and available vaccines make the development of novel efficacious antiviral agents an urgent need. Inhibiting viral attachment and entry is a promising strategy for the development of new treatments and to prevent all subsequent steps in virus infection. Read More

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Mucosal Challenge Ferret Models of Ebola Virus Disease.

Pathogens 2021 Mar 4;10(3). Epub 2021 Mar 4.

Battelle, 1425 Plain City-Georgesville Road, NE, West Jefferson, OH 43162, USA.

Recent studies have shown the domestic ferret () to be a promising small animal model for the study of Ebola virus (EBOV) disease and medical countermeasure evaluation. To date, most studies have focused on traditional challenge routes, predominantly intramuscular and intranasal administration. Here, we present results from a non-clinical pathogenicity study examining oronasal, oral, and ocular mucosal challenge routes in ferrets. Read More

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IgY antibodies against Ebola virus possess post-exposure protection in a murine pseudovirus challenge model and excellent thermostability.

PLoS Negl Trop Dis 2021 03 12;15(3):e0008403. Epub 2021 Mar 12.

Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.

Ebola virus (EBOV) is one of the most virulent pathogens that causes hemorrhagic fever and displays high mortality rates and low prognosis rates in both humans and nonhuman primates. The post-exposure antibody therapies to prevent EBOV infection are considered effective as of yet. However, owing to the poor thermal stability of mammalian antibodies, their application in the tropics has remained limited. Read More

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Ebola infection in pregnancy, an ongoing challenge for both the global health expert and the pregnant woman-A review.

Eur J Obstet Gynecol Reprod Biol 2021 Mar 29;258:111-117. Epub 2020 Dec 29.

Department of Health Sciences, University of Leicester, UK.

A new Ebola outbreak is currently ongoing in the Democratic Republic of Congo, after the most severe outbreak in West Africa in 2014-2016 was controlled. Ebola outbreaks are usually a significant cause of death among pregnant women. The clinical presentation of Ebola Virus infection in pregnancy often mimics common pregnancy related bleeding complications or febrile conditions common in pregnancy. Read More

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A single dose of a vesicular stomatitis virus-based influenza vaccine confers rapid protection against H5 viruses from different clades.

NPJ Vaccines 2020 Jan 10;5(1). Epub 2020 Jan 10.

Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA.

The avian influenza virus outbreak in 1997 highlighted the potential of the highly pathogenic H5N1 virus to cause severe disease in humans. Therefore, effective vaccines against H5N1 viruses are needed to counter the potential threat of a global pandemic. We have previously developed a fast-acting and efficacious vaccine against Ebola virus (EBOV) using the vesicular stomatitis virus (VSV) platform. Read More

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January 2020

Transcriptional Analysis of Lymphoid Tissues from Infected Nonhuman Primates Reveals the Basis for Attenuation and Immunogenicity of an Ebola Virus Encoding a Mutant VP35 Protein.

J Virol 2021 02 24;95(6). Epub 2021 Feb 24.

Department of Molecular Biology and Biochemistry, College of Biological Sciences, University of California, Irvine, Irvine, California, USA

Infection with (EBOV), a member of the family, causes a disease characterized by high levels of viremia, aberrant inflammation, coagulopathy, and lymphopenia. EBOV initially replicates in lymphoid tissues and disseminates via dendritic cells (DCs) and monocytes to liver, spleen, adrenal gland, and other secondary organs. EBOV protein VP35 is a critical immune evasion factor that inhibits type I interferon signaling and DC maturation. Read More

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February 2021

Nonhuman primate to human immunobridging to infer the protective effect of an Ebola virus vaccine candidate.

NPJ Vaccines 2020 Dec 17;5(1):112. Epub 2020 Dec 17.

Janssen Vaccines & Prevention B.V., Leiden, The Netherlands.

It has been proven challenging to conduct traditional efficacy trials for Ebola virus (EBOV) vaccines. In the absence of efficacy data, immunobridging is an approach to infer the likelihood of a vaccine protective effect, by translating vaccine immunogenicity in humans to a protective effect, using the relationship between vaccine immunogenicity and the desired outcome in a suitable animal model. We here propose to infer the protective effect of the Ad26. Read More

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December 2020

Systematic review of Marburg virus vaccine nonhuman primate studies and human clinical trials.

Vaccine 2021 01 9;39(2):202-208. Epub 2020 Dec 9.

Uniformed Services University of the Health Sciences, Bethesda, MD, USA; Walter Reed Army Institute of Research, Silver Spring, MD, USA; George Washington University School of Medicine and Health Sciences, Washington, DC, USA. Electronic address:

Background: Recent deadly outbreaks of Marburg virus underscore the need for an effective vaccine. A summary of the latest research is needed for this WHO priority pathogen. This systematic review aimed to determine progress towards a vaccine for Marburg virus. Read More

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January 2021

Single-Cell Profiling of Ebola Virus Disease In Vivo Reveals Viral and Host Dynamics.

Cell 2020 11 6;183(5):1383-1401.e19. Epub 2020 Nov 6.

Integrated Research Facility, Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, MD 21702, USA.

Ebola virus (EBOV) causes epidemics with high mortality yet remains understudied due to the challenge of experimentation in high-containment and outbreak settings. Here, we used single-cell transcriptomics and CyTOF-based single-cell protein quantification to characterize peripheral immune cells during EBOV infection in rhesus monkeys. We obtained 100,000 transcriptomes and 15,000,000 protein profiles, finding that immature, proliferative monocyte-lineage cells with reduced antigen-presentation capacity replace conventional monocyte subsets, while lymphocytes upregulate apoptosis genes and decline in abundance. Read More

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November 2020

Molecular determinants of Ebola nucleocapsid stability from molecular dynamics simulations.

J Chem Phys 2020 Oct;153(15):155102

Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.

Ebola virus (EBOV) is a human pathogen with the ability to cause hemorrhagic fever and bleeding diathesis in hosts. The life cycle of EBOV depends on its nucleocapsid. The Ebola nucleocapsid consists of a helical assembly of nucleoproteins (NPs) encapsidating single-stranded viral RNA (ssRNA). Read More

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October 2020

Anti-IL-6 Versus Anti-IL-6R Blocking Antibodies to Treat Acute Ebola Infection in BALB/c Mice: Potential Implications for Treating Cytokine Release Syndrome.

Front Pharmacol 2020 23;11:574703. Epub 2020 Sep 23.

Department of Medicine, Columbia University, New York, NY, United States.

Cytokine release syndrome (CRS) is known to be a factor in morbidity and mortality associated with acute viral infections including those caused by filoviruses and coronaviruses. IL-6 has been implicated as a cytokine negatively associated with survival after filovirus and coronavirus infection. However, IL-6 has also been shown to be an important mediator of innate immunity and important for the host response to an acute viral infection. Read More

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September 2020

Comparative performance study of three Ebola rapid diagnostic tests in Guinea.

BMC Infect Dis 2020 Sep 15;20(1):670. Epub 2020 Sep 15.

Center for Sustainable Development, Earth Institute, Columbia University, 475 Riverside Drive, Suite 1040, New York, NY, 10025, USA.

Background: The 2014/15 Ebola outbreak in West Africa resulted in 11,000 deaths and massive strain on local health systems, and the ongoing outbreak in Democratic Republic of Congo has afflicted more than 3000 people. Accurate, rapid Ebola diagnostics suitable for field deployment would enable prompt identification and effective response to future outbreaks, yet remain largely unavailable. The purpose of this study was to assess the accuracy of three novel rapid diagnostic tests (RDTs): an Ebola, an Ebola-Malaria, and a Fever Panel test that includes Ebola, all from a single manufacturer. Read More

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September 2020

Role of Wildlife in Emergence of Ebola Virus in Kaigbono (Likati), Democratic Republic of the Congo, 2017.

Emerg Infect Dis 2020 09;26(9):2205-2209

After the 2017 Ebola virus (EBOV) outbreak in Likati, a district in northern Democratic Republic of the Congo, we sampled small mammals from the location where the primary case-patient presumably acquired the infection. None tested positive for EBOV RNA or antibodies against EBOV, highlighting the ongoing challenge in detecting animal reservoirs for EBOV. Read More

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September 2020

Prior vaccination with rVSV-ZEBOV does not interfere with but improves efficacy of postexposure antibody treatment.

Nat Commun 2020 07 27;11(1):3736. Epub 2020 Jul 27.

Galveston National Laboratory, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-0610, USA.

A replication-competent vesicular stomatitis virus vaccine expressing the Ebola virus (EBOV) glycoprotein (GP) (rVSV-ZEBOV) was successfully used during the 2013-16 EBOV epidemic. Additionally, chimeric and human monoclonal antibodies (mAb) against the EBOV GP have shown promise in animals and humans when administered therapeutically. Uncertainty exists regarding the efficacy of postexposure antibody treatments in the event of a known exposure of a recent rVSV-ZEBOV vaccinee. Read More

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Pyronaridine tetraphosphate efficacy against Ebola virus infection in guinea pig.

Antiviral Res 2020 09 16;181:104863. Epub 2020 Jul 16.

Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, NC, 27606, USA. Electronic address:

The recent outbreaks of the Ebola virus (EBOV) in Africa have brought global visibility to the shortage of available therapeutic options to treat patients infected with this or closely related viruses. We have recently computationally identified three molecules which have all demonstrated statistically significant efficacy in the mouse model of infection with mouse adapted Ebola virus (ma-EBOV). One of these molecules is the antimalarial pyronaridine tetraphosphate (IC range of 0. Read More

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September 2020

A small molecule inhibitor of MyD88 exhibits broad spectrum antiviral activity by up regulation of type I interferon.

Antiviral Res 2020 09 2;181:104854. Epub 2020 Jul 2.

Virology Division, United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Frederick, MD, 21702, USA.

Recent studies highlight that infection with Coxsackievirus B3, Venezuelan equine encephalitis virus (VEEV), Marburg virus, or stimulation using poly I:C (dsRNA), upregulates the signaling adaptor protein MyD88 and impairs the host antiviral type I interferon (IFN) responses. In contrast, MyD88 deficiency (MyD88) increases the type I IFN and survivability of mice implying that MyD88 up regulation limits the type I IFN response. Reasoning that MyD88 inhibition in a virus-like manner may increase type I IFN responses, our studies revealed lipopolysaccharide stimulation of U937 cells or poly I:C stimulation of HEK293-TLR3, THP1 or U87 cells in the presence of a previously reported MyD88 inhibitor (compound 4210) augmented IFN-β and RANTES production. Read More

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September 2020

A Multi-Filovirus Vaccine Candidate: Co-Expression of Ebola, Sudan, and Marburg Antigens in a Single Vector.

Vaccines (Basel) 2020 May 21;8(2). Epub 2020 May 21.

Nuffield Department of Medicine, Jenner Institute, University of Oxford, Oxford OX3 7DQ, UK.

In the infectious diseases field, protective immunity against individual virus species or strains does not always confer cross-reactive immunity to closely related viruses, leaving individuals susceptible to disease after exposure to related virus species. This is a significant hurdle in the field of vaccine development, in which broadly protective vaccines represent an unmet need. This is particularly evident for filoviruses, as there are multiple family members that can cause lethal haemorrhagic fever, including Zaire ebolavirus, Sudan ebolavirus, and Marburg virus. Read More

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Frontline Science: CD40 signaling restricts RNA virus replication in Mϕs, leading to rapid innate immune control of acute virus infection.

J Leukoc Biol 2021 02 22;109(2):309-325. Epub 2020 May 22.

Department of Microbiology and Immunology, University of Iowa, Iowa City, Iowa, USA.

Many acute viral infections target tissue Mϕs, yet the mechanisms of Mϕ-mediated control of viruses are poorly understood. Here, we report that CD40 expressed by peritoneal Mϕs restricts early infection of a broad range of RNA viruses. Loss of CD40 expression enhanced virus replication as early as 12-24 h of infection and, conversely, stimulation of CD40 signaling with an agonistic Ab blocked infection. Read More

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February 2021

An effective CTL peptide vaccine for Ebola Zaire Based on Survivors' CD8+ targeting of a particular nucleocapsid protein epitope with potential implications for COVID-19 vaccine design.

Vaccine 2020 06 28;38(28):4464-4475. Epub 2020 Apr 28.

Flow Pharma, Inc., 3451 Vincent Road, Pleasant Hill, CA 94523, United States; Massachusetts General Hospital, Department of Anesthesia, Critical Care and Pain Medicine, 55 Fruit St, Boston, MA 02114, United States. Electronic address:

The 2013-2016 West Africa EBOV epidemic was the biggest EBOV outbreak to date. An analysis of virus-specific CD8+ T-cell immunity in 30 survivors showed that 26 of those individuals had a CD8+ response to at least one EBOV protein. The dominant response (25/26 subjects) was specific to the EBOV nucleocapsid protein (NP). Read More

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Nanoplasmid Vectors Co-expressing Innate Immune Agonists Enhance DNA Vaccines for Venezuelan Equine Encephalitis Virus and Ebola Virus.

Mol Ther Methods Clin Dev 2020 Jun 15;17:810-821. Epub 2020 Apr 15.

Headquarters, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA.

DNA vaccines expressing codon-optimized Venezuelan equine encephalitis virus (VEEV) and Ebola virus (EBOV) glycoprotein genes provide protective immunity to mice and nonhuman primates when delivered by intramuscular (IM) electroporation (EP). To achieve equivalent protective efficacy in the absence of EP, we evaluated VEEV and EBOV DNA vaccines constructed using minimalized Nanoplasmid expression vectors that are smaller than conventional plasmids used for DNA vaccination. These vectors may also be designed to co-express type I interferon inducing innate immune agonist genes that have an adjuvant effect. Read More

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How virus size and attachment parameters affect the temperature sensitivity of virus binding to host cells: Predictions of a thermodynamic model for arboviruses and HIV.

Authors:
Paul Gale

Microb Risk Anal 2020 Aug 12;15:100104. Epub 2020 Mar 12.

Independent Scientist, 15 Weare Close, Portland, Dorset, DT5 1JP, United Kingdom.

Virus binding to host cells involves specific interactions between viral (glyco)proteins (GP) and host cell surface receptors (Cr) (protein or sialic acid (SA)). The magnitude of the enthalpy of association changes with temperature according to the change in heat capacity (ΔC) on GP/Cr binding, being little affected for avian influenza virus (AIV) haemagglutinin (HA) binding to SA (ΔC = 0 kJ/mol/K) but greatly affected for HIV gp120 binding to CD4 receptor (ΔC = -5.0 kJ/mol/K). Read More

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Towards a thermodynamic mechanistic model for the effect of temperature on arthropod vector competence for transmission of arboviruses.

Authors:
Paul Gale

Microb Risk Anal 2019 Aug 5;12:27-43. Epub 2019 Mar 5.

15 Weare Close, Portland, Dorset DT5 1JP, United Kingdom.

Arboviruses such as West Nile virus (WNV), bluetongue virus (BTV), dengue virus (DENV) and chikungunya virus (CHIKV) infect their arthropod vectors over a range of average temperatures depending on the ambient temperature. How the transmission efficiency of an arbovirus (i.e. Read More

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Acute Plasmodium Infection Promotes Interferon-Gamma-Dependent Resistance to Ebola Virus Infection.

Cell Rep 2020 03;30(12):4041-4051.e4

Department of Microbiology and Immunology, University of Iowa, Iowa City, IA 52242, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242, USA. Electronic address:

During the 2013-2016 Ebola virus (EBOV) epidemic, a significant number of patients admitted to Ebola treatment units were co-infected with Plasmodium falciparum, a predominant agent of malaria. However, there is no consensus on how malaria impacts EBOV infection. The effect of acute Plasmodium infection on EBOV challenge was investigated using mouse-adapted EBOV and a biosafety level 2 (BSL-2) model virus. Read More

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Intradermal Immunization of EBOV VLPs in Guinea Pigs Induces Broader Antibody Responses Against GP Than Intramuscular Injection.

Front Microbiol 2020 27;11:304. Epub 2020 Feb 27.

Department of Microbiology and Immunology and Emory Vaccine Center, School of Medicine, Emory University, Atlanta, GA, United States.

Ebolavirus (EBOV) infection in humans causes severe hemorrhagic fevers with high mortality rates that range from 30 to 80% as shown in different outbreaks. Thus the development of safe and efficacious EBOV vaccines remains an important goal for biomedical research. We have shown in early studies that immunization with insect cell-produced EBOV virus-like particles (VLPs) is able to induce protect vaccinated mice against lethal EBOV challenge. Read More

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February 2020

Ribavirin does not potentiate favipiravir antiviral activity against Ebola virus in non-human primates.

Antiviral Res 2020 05 2;177:104758. Epub 2020 Mar 2.

Université de Paris, IAME, INSERM, F-75018, Paris, France. Electronic address:

Background: In spite of recurrent and dramatic outbreaks, there are no therapeutics approved against Ebola virus disease. Favipiravir, a RNA polymerase inhibitor active against several RNA viruses, recently demonstrated significant but not complete protection in a non-human primate model of Ebola virus disease. In this study, we assessed the benefit of the combination of favipiravir and ribavirin, another broad spectrum antiviral agent, in the same model. Read More

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The antiviral compound remdesivir potently inhibits RNA-dependent RNA polymerase from Middle East respiratory syndrome coronavirus.

J Biol Chem 2020 04 24;295(15):4773-4779. Epub 2020 Feb 24.

Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada

Antiviral drugs for managing infections with human coronaviruses are not yet approved, posing a serious challenge to current global efforts aimed at containing the outbreak of severe acute respiratory syndrome-coronavirus 2 (CoV-2). Remdesivir (RDV) is an investigational compound with a broad spectrum of antiviral activities against RNA viruses, including severe acute respiratory syndrome-CoV and Middle East respiratory syndrome (MERS-CoV). RDV is a nucleotide analog inhibitor of RNA-dependent RNA polymerases (RdRps). Read More

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Longitudinal Human Antibody Repertoire against Complete Viral Proteome from Ebola Virus Survivor Reveals Protective Sites for Vaccine Design.

Cell Host Microbe 2020 02;27(2):262-276.e4

Critical Care Medicine Department, National Institutes of Health Clinical Center, Bethesda, MD 20892, USA; Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.

Evolution of antibody repertoire against the Ebola virus (EBOV) proteome was characterized in an acutely infected patient receiving supportive care alone to elucidate virus-host interactions over time. Differential kinetics are observed for IgM-IgG-IgA epitope diversity, antibody binding, and affinity maturation to EBOV proteins. During acute illness, antibodies predominate to VP40 and glycoprotein (GP). Read More

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February 2020

Safety and immunogenicity of a highly attenuated rVSVN4CT1-EBOVGP1 Ebola virus vaccine: a randomised, double-blind, placebo-controlled, phase 1 clinical trial.

Lancet Infect Dis 2020 04 14;20(4):455-466. Epub 2020 Jan 14.

Department of Virology and Vaccine Development, Profectus BioSciences, Pearl River, NY, USA; Department of Immunology, Profectus BioSciences, Pearl River, NY, USA.

Background: The safety and immunogenicity of a highly attenuated recombinant vesicular stomatitis virus (rVSV) expressing HIV-1 gag (rVSVN4CT1-HIV-1gag1) was shown in previous phase 1 clinical studies. An rVSV vector expressing Ebola virus glycoprotein (EBOV-GP) in place of HIV-1 gag (rVSVN4CT1-EBOVGP1) showed single-dose protection from lethal challenge with low passage Ebola virus in non-human primates. We aimed to evaluate the safety and immunogenicity of the rVSVN4CT1-EBOVGP1 vaccine in healthy adults. Read More

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A single dose of a vesicular stomatitis virus-based influenza vaccine confers rapid protection against H5 viruses from different clades.

NPJ Vaccines 2020 10;5. Epub 2020 Jan 10.

1Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT USA.

The avian influenza virus outbreak in 1997 highlighted the potential of the highly pathogenic H5N1 virus to cause severe disease in humans. Therefore, effective vaccines against H5N1 viruses are needed to counter the potential threat of a global pandemic. We have previously developed a fast-acting and efficacious vaccine against Ebola virus (EBOV) using the vesicular stomatitis virus (VSV) platform. Read More

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January 2020