Serological surveillance in animal and human hosts can be a cost-effective strategy for orthoebolavirus detection, but is challenged by accurate estimates of seroprevalence, potential pauci-symptomatic disease presentation, and antigenic cross-reactivity. Here, we describe the use of an envelope glycoprotein (GP)-based multiplex microsphere immunoassay, consisting of nine filovirus GP antigens for the detection of anti-Ebola virus (EBOV) antibodies in a well-characterized cohort of Guinean Ebola virus disease (EVD) survivors and contacts from the 2013 - 2016 West African EVD outbreak. We examined sensitivity and specificity for the detection of anti-EBOV antibodies by GP expressed as recombinant trimeric ectodomains, yielding an assay performance of 95.
View Article and Find Full Text PDFHuman Ebola virus (EBOV) outbreaks caused by persistent EBOV infection raises questions on the role of zoonotic spillover in filovirus epidemiology. To characterise filovirus zoonotic exposure, we collected cross-sectional serum samples from bushmeat hunters (n = 498) in Macenta Prefecture Guinea, adjacent to the index site of the 2013 EBOV-Makona spillover event. We identified distinct immune signatures (20/498, 4.
View Article and Find Full Text PDFLassa fever virus (LASV) is the causative agent of Lassa fever, a disease endemic in West Africa. Exploring the relationships between environmental factors and LASV transmission across ecologically diverse regions can provide crucial information for the design of appropriate interventions and disease monitoring. We investigated LASV exposure in 2 ecologically diverse regions of Guinea.
View Article and Find Full Text PDFEbola virus disease (EVD) is a complex infectious disease characterized by high inflammation, multiorgan failure, the dysregulation of innate and adaptive immune responses, and coagulation abnormalities. Evidence accumulated over the last 2 decades indicates that, during fatal EVD, the infection of antigen-presenting cells (APC) and the dysregulation of T cell immunity preclude a successful transition between innate and adaptive immunity, which constitutes a key disease checkpoint. In order to better understand the contribution of the APC-T cell crosstalk to EVD pathophysiology, we have developed avatar mice transplanted with human, donor-specific APCs and T cells.
View Article and Find Full Text PDFThe 2013-2016 Ebola virus (EBOV) epidemic in West Africa was unprecedented in case numbers and fatalities, and sporadic outbreaks continue to arise. Antibodies to the EBOV glycoprotein (GP) are strongly associated with survival and their use in immunotherapy is often initially based on their performance in neutralisation assays. Other immune effector functions also contribute to EBOV protection but are more complex to measure.
View Article and Find Full Text PDFBackground: The 2013-16 Ebola virus disease epidemic in west Africa caused international alarm due to its rapid and extensive spread resulting in a significant death toll and social unrest within the affected region. The large number of cases provided an opportunity to study the long-term kinetics of Zaire ebolavirus-specific immune response of survivors in addition to known contacts of those infected with the virus.
Methods: In this observational cohort study, we worked with leaders of Ebola virus disease survivor associations in two regions of Guinea, Guéckédou and Coyah, to recruit survivors of Ebola virus disease, contacts from households of individuals known to have had Ebola virus disease, and individuals who were not knowingly associated with infected individuals or had not had Ebola virus disease symptoms to serve as negative controls.
Ebola virus (EBOV) is an enveloped, single-stranded RNA virus that can cause Ebola virus disease (EVD). It is thought that EVD survivors are protected against subsequent infection with EBOV and that neutralising antibodies to the viral surface glycoprotein (GP) are potential correlates of protection. Serological studies are vital to assess neutralising antibodies targeted to EBOV GP; however, handling of EBOV is limited to containment level 4 laboratories.
View Article and Find Full Text PDFThe last seven years have seen the greatest surge of Ebola virus disease (EVD) cases in equatorial Africa, including the 2013-2016 epidemic in West Africa and the recent epidemics in the Democratic Republic of Congo (DRC). The vaccine clinical trials that took place in West Africa and the DRC, as well as follow-up studies in collaboration with EVD survivor communities, have for the first time allowed researchers to compare immune memory induced by natural infection and vaccination. These comparisons may be relevant to evaluate the putative effectiveness of vaccines and candidate medical countermeasures such as convalescent plasma transfer.
View Article and Find Full Text PDFBackground: To date, epidemiological studies at the index site of the 2013-16 west African Ebola outbreak in Meliandou, Guinea, have been restricted in their scope. We aimed to determine the occurrence of previously undocumented Ebola virus disease (EVD) cases and infections, and to reconstruct transmission events.
Methods: This cross-sectional seroprevalence survey of the adult population of Meliandou used a highly specific oral fluid test and detailed interviews of all households in the village and key informants.
The family Arteriviridae harbors a rapidly expanding group of viruses known to infect a divergent group of mammals, including horses, pigs, possums, primates, and rodents. Hosts infected with arteriviruses present with a wide variety of (sub) clinical symptoms, depending on the virus causing the infection and the host being infected. In this study, we determined the complete genome sequences of three variants of a previously unknown virus found in Olivier's shrews (Crocidura olivieri guineensis) sampled in Guinea.
View Article and Find Full Text PDFIn this study, samples from the 2013-2016 West African Ebola virus outbreak from patients in Guinea with Ebola virus disease (EVD) were analyzed to discover and classify what other pathogens were present. Throat swabs were taken from deceased EVD patients, and peripheral blood samples were analyzed that had been taken from patients when they presented at the treatment center with acute illness. High-throughput RNA sequencing (RNA-seq) and bioinformatics were used to identify the potential microorganisms.
View Article and Find Full Text PDFBackground: In 2014-2015, we assessed favipiravir tolerance and efficacy in patients with Ebola virus (EBOV) disease (EVD) in Guinea (JIKI trial). Because the drug had never been used before for this indication and that high concentrations of the drugs were needed to achieve antiviral efficacy against EBOV, a pharmacokinetic model had been used to propose relevant dosing regimen. Here we report the favipiravir plasma concentrations that were achieved in participants in the JIKI trial and put them in perspective with the model-based targeted concentrations.
View Article and Find Full Text PDFBackground: By January, 2016, all known transmission chains of the Ebola virus disease (EVD) outbreak in west Africa had been stopped. However, there is concern about persistence of Ebola virus in the reproductive tract of men who have survived EVD. We aimed to use biostatistical modelling to describe the dynamics of Ebola virus RNA load in seminal fluid, including clearance parameters.
View Article and Find Full Text PDFA 9-month-old infant died from Ebola virus (EBOV) disease with unknown epidemiological link. While her parents did not report previous illness, laboratory investigations revealed persisting EBOV RNA in the mother's breast milk and the father's seminal fluid. Genomic analysis strongly suggests EBOV transmission to the child through breastfeeding.
View Article and Find Full Text PDFBackground: A unit of the European Mobile Laboratory (EMLab) consortium was deployed to the Ebola virus disease (EVD) treatment unit in Guéckédou, Guinea, from March 2014 through March 2015.
Methods: The unit diagnosed EVD and malaria, using the RealStar Filovirus Screen reverse transcription-polymerase chain reaction (RT-PCR) kit and a malaria rapid diagnostic test, respectively.
Results: The cleaned EMLab database comprised 4719 samples from 2741 cases of suspected EVD from Guinea.
The Ebola virus disease epidemic in West Africa is the largest on record, responsible for over 28,599 cases and more than 11,299 deaths. Genome sequencing in viral outbreaks is desirable to characterize the infectious agent and determine its evolutionary rate. Genome sequencing also allows the identification of signatures of host adaptation, identification and monitoring of diagnostic targets, and characterization of responses to vaccines and treatments.
View Article and Find Full Text PDFWe report 2 cases of Ebola viral disease (EVD) in pregnant women who survived, initially with intact pregnancies. Respectively 31-32 days after negativation of the maternal blood EVD-polymerase chain reaction (PCR) both patients delivered a stillborn fetus with persistent EVD-PCR amniotic fluid positivity.
View Article and Find Full Text PDFWest Africa is currently witnessing the most extensive Ebola virus (EBOV) outbreak so far recorded. Until now, there have been 27,013 reported cases and 11,134 deaths. The origin of the virus is thought to have been a zoonotic transmission from a bat to a two-year-old boy in December 2013 (ref.
View Article and Find Full Text PDFBackground: Reliable reverse transcription polymerase chain reaction (RT-PCR)-based diagnosis of Ebola virus infection currently requires a blood sample obtained by intravenous puncture. During the current Ebola outbreak in Guinea, we evaluated the usability of capillary blood samples collected from fingersticks of patients suspected of having Ebola virus disease (EVD) for field diagnostics during an outbreak emergency.
Methods: A total of 120 venous and capillary blood samples were collected from 53 patients admitted to the Ebola Treatment Centre in Guéckédou, Guinea, between July and August 2014.