Clinical features and viral kinetics in a rapidly cured patient with Ebola virus disease: a case report

Detection of SARS-CoV-2 Genome in Stool and Plasma Samples of Laboratory Confirmed Iranian COVID-19 Patients

Coronavirus disease 2019 (COVID19), caused by the severe acute respiratory syndrome coronavirus 2 (SARSCoV2), was first discovered in China in late 2019 and quickly spread worldwide. Although nasopharyngeal swab sampling is still the most popular approach identify SARS-CoV-2 carriers, other body samples may reveal the virus genome, indicating the potential for virus transmission via non-respiratory samples. In this study, researchers looked at the presence and degree of SARS-CoV-2 genome in stool and plasma samples from 191 Iranian COVID-19 patients, and looked for a link between these results and the severity of their disease. SARS-CoV-2 RNA shedding in feces and plasma of COVID-19 patients was assessed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Medical data were collected and evaluated, including Clinical features, demographics, radiological, and laboratory findings of the patients. Plasma samples from 117 confirmed laboratory patients were evaluated and 24 out of 117 patients (20.51%) tested positive for SARS-COV-2 RNA. Besides, 20 out of 74 patients (27.03%) tested positive for SARS-COV-2 RNA in stool samples. There seems to be no relationship between the presence of SARS-CoV-2 genome in fecal and plasma samples of Covid-19 patients and the severity of illness. We provide evidence of the SARS-CoV-2 genome presence in stool and plasma samples of Iranian COVID-19 patients.

Comparison and Evaluation of Real-Time Taqman PCR for Detection and Quantification of Ebolavirus

Given that ebolavirus causes severe and frequently lethal disease, its rapid and accurate detection using available and validated methods is essential for controlling infection. Real-time reverse-transcription PCR (RT-PCR) has proven to be an invaluable tool for ebolaviruses diagnostics. Many assays with different targets have been developed, but they have not been externally compared or validated, and limits of detection are not uniformly reported. Here we compared and evaluated the sensitivity, reproducibility and specificity of 23 in-house assays under the same conditions. Our results showed that these assays were highly gene- and species- specific when evaluated using in vitro RNA transcripts and viral RNA, and the potential limits of detection were uniformly reported ranging from 102 to 106 in vitro synthesized RNA transcripts copies perμL and 1-100 TCID50/mL. The comparison of these assays indicated that those targeting the more conservative NP gene could be the better option for EVD case definition and quantitative measurement because of its higher sensitivity for the same species. Our analysis could contribute to the standardization of ebolavirus detection and quantification assays, which can offer a better understanding of the meaning of results across laboratories and time points, as well as make them easy to implement, especially under outbreak conditions.

Targeting Ebola virus replication through pharmaceutical intervention

Introduction. The consistent emergence/reemergence of filoviruses into a world that previously lacked an approved pharmaceutical intervention parallels an experience repeatedly played-out for most other emerging pathogenic zoonotic viruses. Investment to preemptively develop effective and low-cost prophylactic and therapeutic interventions against viruses that have high potential for emergence and societal impact should be a priority.Areas covered. Candidate drugs can be characterized into those that interfere with cellular processes required for Ebola virus (EBOV) replication (host-directed), and those that directly target virally encoded functions (direct-acting). We discuss strategies to identify pharmaceutical interventions for EBOV infections. PubMed/Web of Science databases were searched to establish a detailed catalog of these interventions.Expert opinion. Many drug candidates show promising in vitro inhibitory activity, but experience with EBOV shows the general lack of translation to in vivo efficacy for host-directed repurposed drugs. Better translation is seen for direct-acting antivirals, in particular monoclonal antibodies. The FDA-approved monoclonal antibody treatment, Inmazeb™ is a success story that could be improved in terms of impact on EBOV-associated disease and mortality, possibly by combination with other direct-acting agents targeting distinct aspects of the viral replication cycle. Costs need to be addressed given EBOV emergence primarily in under-resourced countries.

Amplification-free RNA detection with CRISPR-Cas13

CRISPR-based nucleic-acid detection is an emerging technology for molecular diagnostics. However, these methods generally require several hours and could cause amplification errors, due to the pre-amplification of target nucleic acids to enhance the detection sensitivity. Here, we developed a platform that allows “CRISPR-based amplification-free digital RNA detection (SATORI)”, by combining CRISPR-Cas13-based RNA detection and microchamber-array technologies. SATORI detected single-stranded RNA targets with maximal sensitivity of ~10 fM in <5 min, with high specificity. Furthermore, the simultaneous use of multiple different guide RNAs enhanced the sensitivity, thereby enabling the detection of the SARS-CoV-2 N-gene RNA at ~5 fM levels. Therefore, we hope SATORI will serve as a powerful class of accurate and rapid diagnostics.

The authors develop a platform (SATORI) that enables accurate and rapid detection of single-stranded RNA at a single-molecule level without a pre-amplification step. As a proof-of-concept, they demonstrate its utility in detecting the SARS-CoV-2 N gene at a minimum concentration of ~5 fM, which is much lower than other amplification-free CRISPR-Cas-based methods.

Effect of an E-Learning Module on Personal Protective Equipment Proficiency Among Prehospital Personnel: Web-Based Randomized Controlled Trial

Background

To avoid misuse of personal protective equipment (PPE), ensure health care workers’ safety, and avoid shortages, effective communication of up-to-date infection control guidelines is essential. As prehospital teams are particularly at risk of contamination given their challenging work environment, a specific gamified electronic learning (e-learning) module targeting this audience might provide significant advantages as it requires neither the presence of learners nor the repetitive use of equipment for demonstration.

Objective

The aim of this study was to evaluate whether a gamified e-learning module could improve the rate of adequate PPE choice by prehospital personnel in the context of the coronavirus disease (COVID-19) pandemic.

Methods

This was an individual-level randomized, controlled, quadruple-blind (investigators, participants, outcome assessors, and data analysts) closed web-based trial. All emergency prehospital personnel working in Geneva, Switzerland, were eligible for inclusion, and were invited to participate by email in April 2020. Participants were informed that the study aim was to assess their knowledge regarding PPE, and that they would be presented with both the guidelines and the e-learning module, though they were unaware that there were two different study paths. All participants first answered a preintervention quiz designed to establish their profile and baseline knowledge. The control group then accessed the guidelines before answering a second set of questions, and were then granted access to the e-learning module. The e-learning group was shown the e-learning module right after the guidelines and before answering the second set of questions.

Results

Of the 291 randomized participants, 176 (60.5%) completed the trial. There was no significant difference in baseline knowledge between groups. Though the baseline proportion of adequate PPE choice was high (75%, IQR 50%-75%), participants’ description of the donning sequence was in most cases incorrect. After either intervention, adequate choice of PPE increased significantly in both groups (P<.001). Though the median of the difference in the proportion of correct answers was slightly higher in the e-learning group (17%, IQR 8%-33% versus 8%, IQR 8%-33%), the difference was not statistically significant (P=.27). Confidence in the ability to use PPE was maintained in the e-learning group (P=.27) but significantly decreased in the control group (P=.04).

Conclusions

Among prehospital personnel with an already relatively high knowledge of and experience with PPE use, both web-based study paths increased the rate of adequate choice of PPE. There was no major added value of the gamified e-learning module apart from preserving participants' confidence in their ability to correctly use PPE.

Le service de soins intensifs (réanimation) adultes à Genève, Suisse

Le complexe hospitalier universitaire de Genève est le plus grand de Suisse et est couplé à la Faculté de Médecine de l’Université de Genève. Le service des soins intensifs adultes est un service médico-chirurgical et comprend 32 lits répartis en trois unités : une unité de neuro-réanimation, une unité de médecine intensive cardiovasculaire et une unité polyvalente s’occupant des malades qui n’ont pas les spécificités des deux autres secteurs. Le service accueille plus de 2200 patients annuellement, en moyenne pour 4 jours. Le taux de mortalité est de 7,5 % en 2019 pour un SAPS2 moyen de 44 points. Une quatrième unité, non-géographique celle-là, s’occupe des besoins spécifiques des patients « long séjour » et de leurs proches ainsi que de la consultation post-réanimation, 6 et 12 mois après l’hospitalisation. Les infirmières sont spécialisées en soins intensifs et s’occupent en moyenne d’1,5 patients la journée et de 2 patients la nuit. Le service est un centre de formation pour les intensivistes suisses et un centre de recherche clinique de qualité.

Combating biothreat pathogens: ongoing efforts for countermeasure development and unique challenges

Research to discover and develop antibacterial and antiviral drugs with potent activity against pathogens of biothreat concern presents unique methodological and process-driven challenges. Herein, we review laboratory approaches for finding new antibodies, antibiotics, and antiviral molecules for pathogens of biothreat concern. Using high-throughput screening techniques, molecules that directly inhibit a pathogen’s entry, replication, or growth can be identified. Alternatively, molecules that target host proteins can be interesting targets for development when countering biothreat pathogens, due to the modulation of the host immune response or targeting proteins that interfere with the pathways required by the pathogen for replication. Monoclonal and cocktail antibody therapies approved by the Food and Drug Administration for countering anthrax and under development for treatment of Ebola virus infection are discussed. A comprehensive tabular review of current in vitro, in vivo, pharmacokinetic and efficacy datasets has been presented for biothreat pathogens of greatest concern. Finally, clinical trials and animal rule or traditional drug approval pathways are also reviewed.

Opinions; interpretations; conclusions; and recommendations are those of the authors and are not necessarily endorsed by the US Army.

Perspectives towards antiviral drug discovery against Ebola virus

Ebola virus disease (EVD), caused by Ebola viruses, resulted in more than 11 500 deaths according to a recent 2018 WHO report. With mortality rates up to 90%, it is nowadays one of the most deadly infectious diseases. However, no Food and Drug Administration‐approved Ebola drugs or vaccines are available yet with the mainstay of therapy being supportive care. The high fatality rate and absence of effective treatment or vaccination make Ebola virus a category‐A biothreat pathogen. Fortunately, a series of investigational countermeasures have been developed to control and prevent this global threat. This review summarizes the recent therapeutic advances and ongoing research progress from research and development to clinical trials in the development of small‐molecule antiviral drugs, small‐interference RNA molecules, phosphorodiamidate morpholino oligomers, full‐length monoclonal antibodies, and vaccines. Moreover, difficulties are highlighted in the search for effective countermeasures against EVD with additional focus on the interplay between available in silico prediction methods and their evidenced potential in antiviral drug discovery.

Anti-Ebola therapy for patients with Ebola virus disease: a systematic review

Background

Management of Ebola virus disease (EVD) has historically focused on infection prevention, case detection and supportive care. Several specific anti-Ebola therapies have been investigated, including during the 2014–2016 West African outbreak. Our objective was to conduct a systematic review of the effect of anti-Ebola virus therapies on clinical outcomes to guide their potential use and future evaluation.

Methods

We searched PubMed, EMBASE, Global Health, Cochrane Library, African Index Medicus, WHOLIS (inception-9 April 2018), and trial registries for observational studies or clinical trials, in any language, that enrolled patients with confirmed EVD who received therapy targeting Ebola virus and reported on mortality, symptom duration, or adverse effects.

Results

From 11,257 citations and registered trials, we reviewed 55 full-text citations, of which 35 met eligibility criteria (1 randomized clinical trial (RCT), 8 non-randomized comparative studies, 9 case series and 17 case reports) and collectively examined 21 anti-Ebola virus agents. The 31 studies performed during the West African outbreak reported on 4.8% (1377/28616) of all patients with Ebola. The only RCT enrolled 72 patients (0.25% of all patients with Ebola) and compared the monoclonal antibody ZMapp vs. standard care (mortality, 22% vs. 37%; 95% confidence interval for risk difference, − 36 to 7%). Studies of convalescent plasma, interferon-β-1a, favipiravir, brincidofovir, artesunate-amodiaquine and TKM-130803 were associated with at least moderate risk of bias.

Conclusions

Research evaluating anti-Ebola virus agents has reached very few patients with EVD, and inferences are limited by non-randomized study designs. ZMapp has the most promising treatment signal.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-3980-9) contains supplementary material, which is available to authorized users.

Antiviral Agents Against Ebola Virus Infection: Repositioning Old Drugs and Finding Novel Small Molecules

Ebola virus (EBOV) causes a deadly hemorrhagic syndrome in humans with mortality rate up to 90%. First reported in Zaire in 1976, EBOV outbreaks showed a fluctuating trend during time and fora long period it was considered a tragic disease confined to the isolated regions of the African continent where the EBOV fear was perpetuated among the poor communities. The extreme severity of the recent 2014-16 EBOV outbreak in terms of fatality rate and rapid spread out of Africa led to the understanding that EBOV is a global health risk and highlights the necessity to find countermeasures against it. In the recent years, several small molecules have been shown to display in vitro and in vivo efficacy against EBOV and some of them have advanced into clinical trials. In addition, also existing drugs have been tested for their anti-EBOV activity and were shown to be promising candidates. However, despite the constant effort addressed to identify anti-EBOV therapeutics, no approved drugs are available against EBOV yet. In this chapter, we describe the main EBOV life cycle steps, providing a detailed picture of the druggable viral and host targets that have been explored so far by different technologies. We then summarize the small molecules, nucleic acid oligomers, and antibody-based therapies reported to have an effect either in in silico, or in biochemical and cell-based assays or in animal models and clinical trials, listing them according to their demonstrated or putative mechanism of action.

Efficacy of favipiravir (T-705) in nonhuman primates infected with Ebola virus or Marburg virus

Favipiravir is a broad-spectrum antiviral agent that has demonstrated efficacy against Ebola virus (EBOV) in rodents. However, there are no published reports of favipiravir efficacy for filovirus infection of nonhuman primates (NHPs). Here we evaluated the pharmacokinetic profile of favipiravir in NHPs, as well as in vivo efficacy against two filoviruses, EBOV and Marburg virus (MARV). While no survival benefit was observed in two studies employing once- or twice-daily oral dosing of favipiravir during EBOV infection of NHPs, an antiviral effect was observed in terms of extended time-to-death and reduced levels of viral RNA. However, oral dosing in biosafety level-4 (BSL-4) presents logistical and technical challenges, and repeated anesthesia events may potentially worsen survival outcome in animals. For the third study of treatment of MARV infection, we therefore made use of catheters, jackets, and tethers for intravenous (IV) dosing and blood collection, which minimized the requirement for repeated anesthesia events. When MARV infection was treated with IV favipiravir, five of six animals (83%) survived infection, while all untreated NHPs succumbed. An accompanying report presents the results of favipiravir treatment of EBOV infection in mice.

Treatment-focused Ebola trials, supportive care and future of filovirus care

INTRODUCTION

During the 2014-2016 Ebolavirus (EBOV) outbreak, several candidate therapeutics were used in EBOV-infected patients in clinical trials and under expanded access for emergency use. This review will focus briefly on medications used during the outbreak. We will discuss current therapeutic candidates and their status and will then turn to a related and essential topic: supportive care and the standard of care for filovirus infected patients. Potential benefits and pitfalls of combination therapies for filoviruses will be discussed. Areas covered: Clinical trials of therapeutics targeting EBOV; clinical usage of therapeutics during recent EBOV outbreak; potential need for combination therapy; role of supportive care in treatment of Ebola virus disease (EVD). Expert commentary: In the absence of another large scale EBOV outbreak, the path to therapeutic product licensure in the United States of America (USA) would need to be via the FDA Animal Rule. However, human data may be needed to supplement animal data. The future of filovirus therapeutics may therefore benefit by establishing the ability to implement clinical trials in an outbreak setting in a timely fashion. Supportive care guidelines for filovirus infection should be defined and established as standard of care for treatment of EVD.

Ebola virus disease: an update on post-exposure prophylaxis

The massive outbreak of Ebola virus disease in west Africa between 2013 and 2016 resulted in intense efforts to evaluate the efficacy of several specific countermeasures developed through years of preclinical work, including the first clinical trials for therapeutics and vaccines. In this Review, we discuss how the experience and data generated from that outbreak have helped to advance the understanding of the use of these countermeasures for post-exposure prophylaxis against Ebola virus infection. In future outbreaks, post-exposure prophylaxis could play an important part in reducing community transmission of Ebola virus by providing more immediate protection than does immunisation as well as providing additional protection for health-care workers who are inadvertently exposed over the course of their work. We propose provisional guidance for use of post-exposure prophylaxis in Ebola virus disease and identify the priorities for future preparedness and further research.

Insights from clinical research completed during the west Africa Ebola virus disease epidemic

The west Africa Ebola virus disease (EVD) epidemic was extraordinary in scale. Now that the epidemic has ended, it is a relevant time to examine published studies with direct relevance to clinical care and, more broadly, to examine the implications of the clinical research response mounted. Clinically relevant research includes literature detailing risk factors for and clinical manifestations of EVD, laboratory and other investigation findings in patients, experimental vaccine and therapeutic clinical trials, and analyses of survivor syndrome. In this Review, we discuss new insights from patient-oriented research completed during the west Africa epidemic, identify ongoing knowledge gaps, and suggest priorities for future research.

Discovering Drugs for the Treatment of Ebola Virus

Purpose of review

Ebola virus, a member of the Filoviridae family, is a causative agent of severe viral hemorrhagic fever in humans. Over the past 40 years, the virus has been linked to several high mortality outbreaks in Africa with the recent West African outbreak resulting in over 11,000 deaths. This review provides a summary of the status of the drug discovery and development process for therapeutics for Ebola virus disease, with a focus on the strategies being used and the challenges facing each stage of the process.

Recent findings

Despite the wealth of in vitro efficacy data, preclinical data in animal models, and human clinical data, no therapeutics have been approved for the treatment of Ebola virus disease. However, several promising candidates, such as ZMapp and GS-5734, have advanced into ongoing clinical trials.

Summary

The gravity of the 2014-2016 outbreak spurred a heightened effort to identify and develop new treatments for Ebola virus disease, including small molecules, immunotherapeutics, host factors, and clinical disease management options.

Disclaimer

Opinions, interpretations, conclusions, and recommendations are those of the authors and are not necessarily endoresed by the U.S. Army.

Clinical, virological, and biological parameters associated with outcomes of Ebola virus infection in Macenta, Guinea

BACKGROUND. The pathogenesis of Ebola virus (EBOV) disease (EVD) is poorly characterized. The establishment of well-equipped diagnostic laboratories close to Ebola treatment centers (ETCs) has made it possible to obtain relevant virological and biological data during the course of EVD and to assess their association with the clinical course and different outcomes of the disease. METHODS. We were responsible for diagnosing EBOV infection in patients admitted to two ETCs in forested areas of Guinea. The pattern of clinical signs was recorded, and an etiological diagnosis was established by RT-PCR for EBOV infection or a rapid test for malaria and typhoid fever. Biochemical analyses were also performed. RESULTS. We handled samples from 168 patients between November 29, 2014, and January 31, 2015; 97 patients were found to be infected with EBOV, with Plasmodium falciparum coinfection in 18%. Overall mortality for EVD cases was 58%, rising to 86% if P. falciparum was also present. Viral load was higher in fatal cases of EVD than in survivors, and fatal cases were associated with higher aspartate aminotransferase (AST) and alanine aminotransferase (ALT), C-reactive protein (CRP), and IL-6 levels. Furthermore, regardless of outcome, EVD was characterized by higher creatine kinase (CPK), amylase, and creatinine levels than in febrile patients without EVD, with higher blood urea nitrogen (BUN) levels in fatal cases of EVD only. CONCLUSION. These findings suggest that a high viral load at admission is a marker of poor EVD prognosis. In addition, high AST, ALT, CRP, and IL-6 levels are associated with a fatal outcome of EVD. Damage to the liver and other tissues, with massive rhabdomyolysis and, probably, acute pancreatitis, is associated with EVD and correlated with disease severity. Finally, biochemical analyses provide substantial added value at ETCs, making it possible to improve supportive rehydration and symptomatic care for patients. FUNDING. The French Ministry of Foreign Affairs, the Agence Française de Développement, and Institut Pasteur.

Filovirus proteins for antiviral drug discovery: Structure/function bases of the replication cycle

Filoviruses are important pathogens that cause severe and often fatal hemorrhagic fever in humans, for which no approved vaccines and antiviral treatments are yet available. In an earlier article (Martin et al., Antiviral Research, 2016), we reviewed the role of the filovirus surface glycoprotein in replication and as a target for drugs and vaccines. In this review, we focus on recent findings on the filovirus replication machinery and how they could be used for the identification of new therapeutic targets and the development of new antiviral compounds. First, we summarize the recent structural and functional advances on the molecules involved in filovirus replication/transcription cycle, particularly the NP, VP30, VP35 proteins, and the "large" protein L, which harbors the RNA-dependent RNA polymerase (RdRp) and mRNA capping activities. These proteins are essential for viral mRNA synthesis and genome replication, and consequently they constitute attractive targets for drug design. We then describe how these insights into filovirus replication mechanisms and the structure/function characterization of the involved proteins have led to the development of new and innovative antiviral strategies that may help reduce the filovirus disease case fatality rate through post-exposure or prophylactic treatments.

Characteristics and Outcomes of Pediatric Patients With Ebola Virus Disease Admitted to Treatment Units in Liberia and Sierra Leone: A Retrospective Cohort Study

BACKGROUND

The clinical and virologic characteristics of Ebola virus disease (EVD) in children have not been thoroughly documented.

METHODS

Consecutive children aged <18 years with real-time polymerase chain reaction (RT-PCR)-confirmed EVD were enrolled retrospectively in 5 Ebola treatment units in Liberia and Sierra Leone in 2014/2015. Data collection and medical management were based on standardized International Medical Corps protocols. We performed descriptive statistics, multivariate logistic regression, and Kaplan-Meier survival analyses.

RESULTS

Of 122 children enrolled, the median age was 7 years and one-third were aged <5 years. The female-to-male ratio was 1.3. The most common clinical features at triage and during hospitalization were fever, weakness, anorexia, and diarrhea, although 21% of patients were initially afebrile and 6 patients remained afebrile. Bleeding was rare at presentation (5%) and manifested subsequently in fewer than 50%. The overall case fatality rate was 57%. Factors associated with death in bivariate analyses were age <5 years, bleeding at any time during hospitalization, and high viral load. After adjustment with logistic regression modeling, the odds of death were 14.8-fold higher if patients were aged <5 years, 5-fold higher if the patient had any evidence of bleeding, and 5.2-fold higher if EVD RT-PCR cycle threshold value was ≤20. Plasmodium parasitemia had no impact on EVD outcomes.

CONCLUSIONS

Age <5 years, bleeding, and high viral loads were poor prognostic indicators of children with EVD. Research to understand mechanisms of these risk factors and the impact of dehydration and electrolyte imbalance will improve health outcomes.

Ebolavirus: An Overview of Molecular and Clinical Pathogenesis

Ebolaviruses cause severe, often fatal hemorrhagic fever in Central, East, and West Africa. Until recently, they have been viewed as rare but highly pathogenic infections with regional, but limited, global public health impact. This view has changed with the emergence of the first epidemic of Ebola hemorrhagic fever in West Africa. In this chapter we provide an introduction of the pathogenesis of ebolaviruses as well as a description of clinical disease features. We also describe the current animal models used in ebolavirus research, detailing each model's unique strengths and weaknesses. We focus on Ebola virus representing the type species Zaire ebolavirus of the genus Ebolavirus, as most work relates to this pathogen.

Clinical and Virological Characteristics of Ebola Virus Disease Patients Treated With Favipiravir (T-705)-Sierra Leone, 2014

BACKGROUND

 During 2014-2015, an outbreak of Ebola virus disease (EVD) swept across parts of West Africa. No approved antiviral drugs are available for Ebola treatment currently.

METHODS

 A retrospective clinical case series was performed for EVD patients in Sierra Leone-China Friendship Hospital. Patients with confirmed EVD were sequentially enrolled and treated with either World Health Organization (WHO)-recommended supportive therapy (control group) from 10 to 30 October, or treated with WHO-recommended therapy plus favipiravir (T-705) from 1 to 10 November 2014. Survival and virological characteristics were observed for 85 patients in the control group and 39 in the T-705 treatment group.

RESULTS

 The overall survival rate in the T-705 treatment group was higher than that of the control group (56.4% [22/39] vs 35.3% [30/85]; P = .027). Among the 35 patients who finished all designed endpoint observations, the survival rate in the T-705 treatment group (64.8% [11/17]) was higher than that of the control group (27.8% [5/18]). Furthermore, the average survival time of the treatment group (46.9 ± 5.6 days) was longer than that of the control group (28.9 ± 4.7 days). Most symptoms of patients in the treatment group improved significantly. Additionally, 52.9% of patients who received T-705 had a >100-fold viral load reduction, compared with only 16.7% of patients in the control group.

CONCLUSIONS

 Treatment of EVD with T-705 was associated with prolonged survival and markedly reduced viral load, which makes a compelling case for further randomized controlled trials of T-705 for treating EVD.

Ebola Virus Shedding and Transmission: Review of Current Evidence

BACKGROUND

The magnitude of the 2013-2016 Ebola virus disease outbreak in West Africa was unprecedented, with >28 500 reported cases and >11 000 deaths. Understanding the key elements of Ebola virus transmission is necessary to implement adequate infection prevention and control measures to protect healthcare workers and halt transmission in the community.

METHODS

We performed an extensive PubMed literature review encompassing the period from discovery of Ebola virus, in 1976, until 1 June 2016 to evaluate the evidence on modes of Ebola virus shedding and transmission.

FINDINGS

Ebola virus has been isolated by cell culture from blood, saliva, urine, aqueous humor, semen, and breast milk from infected or convalescent patients. Ebola virus RNA has been noted in the following body fluids days or months after onset of illness: saliva (22 days), conjunctiva/tears (28 days), stool (29 days), vaginal fluid (33 days), sweat (44 days), urine (64 days), amniotic fluid (38 days), aqueous humor (101 days), cerebrospinal fluid (9 months), breast milk (16 months [preliminary data]), and semen (18 months). Nevertheless, the only documented cases of secondary transmission from recovered patients have been through sexual transmission. We did not find strong evidence supporting respiratory or fomite-associated transmission.

Monoclonal antibodies for the treatment of Ebola virus disease

INTRODUCTION

To date, the management of patients with suspected or confirmed Ebolavirus disease (EVD) depends on quarantine, symptomatic management and supportive care, as there are no approved vaccines or treatments available for human use. However, accelerated by the recent large outbreak in West Africa, significant progress has been made towards vaccine development but also towards specific treatment with convalescent plasma and monoclonal antibodies. Areas covered: We describe recent developments in monoclonal antibody treatment for EVD, encompassing mAb114 and the MB-003, ZMAb, ZMapp™ and MIL-77E cocktails. Expert opinion: Preventive measures, are, and will remain essential to curb EVD outbreaks; even more so with vaccine development progressing. However, research for treatment options must not be neglected. Small-scale animal and individual human case studies show that monoclonal antibodies (mAbs) can be effective for EVD treatment; thus justifying exploration in clinical trials. Potential limitations are that high doses may be needed to yield clinical efficacy; epitope mutations might reduce efficacy; and constant evolution of (outbreak-specific) mAb mixtures might be required. Interim advice based on the clinical experience to date is that treatment of patients with mAbs is sensible, provided those could be made available in the necessary amounts in time.

Evaluation of RealStar Reverse Transcription-Polymerase Chain Reaction Kits for Filovirus Detection in the Laboratory and Field

Background. Diagnosis of Ebola virus (EBOV) disease (EVD) requires laboratory testing.

Methods. The RealStar Filovirus Screen reverse transcription–polymerase chain reaction (RT-PCR) kit and the derived RealStar Zaire Ebolavirus RT-PCR kit were validated using in vitro transcripts, supernatant of infected cell cultures, and clinical specimens from patients with EVD.

Results. The Filovirus Screen kit detected EBOV, Sudan virus, Taï Forest virus, Bundibugyo virus, Reston virus, and Marburg virus and differentiated between the genera Ebolavirus and Marburgvirus. The amount of filovirus RNA that could be detected with a probability of 95% ranged from 11 to 67 RNA copies/reaction on a LightCycler 480 II. The Zaire Ebolavirus kit is based on the Filovirus Screen kit but was optimized for detection of EBOV. It has an improved signal-to-noise ratio at low EBOV RNA concentrations and is somewhat more sensitive than the Filovirus kit. Both kits show significantly lower analytical sensitivity on a SmartCycler II. Clinical evaluation revealed that the SmartCycler II, compared with other real-time PCR platforms, decreases the clinical sensitivity of the Filovirus Screen kit to diagnose EVD at an early stage.

Conclusions. The Filovirus Screen kit detects all human-pathogenic filoviruses with good analytical sensitivity if performed on an appropriate real-time PCR platform. High analytical sensitivity is important for early diagnosis of EVD.

Ebola virus disease and critical illness

As of 20 May 2016 there have been 28,646 cases and 11,323 deaths resulting from the West African Ebola virus disease (EVD) outbreak reported to the World Health Organization. There continue to be sporadic flare-ups of EVD cases in West Africa.EVD presentation is nonspecific and characterized initially by onset of fatigue, myalgias, arthralgias, headache, and fever; this is followed several days later by anorexia, nausea, vomiting, diarrhea, and abdominal pain. Anorexia and gastrointestinal losses lead to dehydration, electrolyte abnormalities, and metabolic acidosis, and, in some patients, acute kidney injury. Hypoxia and ventilation failure occurs most often with severe illness and may be exacerbated by substantial fluid requirements for intravascular volume repletion and some degree of systemic capillary leak. Although minor bleeding manifestations are common, hypovolemic and septic shock complicated by multisystem organ dysfunction appear the most frequent causes of death.Males and females have been equally affected, with children (0-14 years of age) accounting for 19 %, young adults (15-44 years) 58 %, and older adults (≥45 years) 23 % of reported cases. While the current case fatality proportion in West Africa is approximately 40 %, it has varied substantially over time (highest near the outbreak onset) according to available resources (40-90 % mortality in West Africa compared to under 20 % in Western Europe and the USA), by age (near universal among neonates and high among older adults), and by Ebola viral load at admission.While there is no Ebola virus-specific therapy proven to be effective in clinical trials, mortality has been dramatically lower among EVD patients managed with supportive intensive care in highly resourced settings, allowing for the avoidance of hypovolemia, correction of electrolyte and metabolic abnormalities, and the provision of oxygen, ventilation, vasopressors, and dialysis when indicated. This experience emphasizes that, in addition to evaluating specific medical treatments, improving the global capacity to provide supportive critical care to patients with EVD may be the greatest opportunity to improve patient outcomes.

Ebola Virus Disease: Therapeutic and Potential Preventative Opportunities

The 2014 Ebola virus disease (EVD) epidemic in West Africa was unprecedented in its geographical distribution, scale, and toll on public health infrastructure. Standard public health measures were rapidly overwhelmed, and many projections on outbreak progression through the region were dire. At the beginning of the outbreak there were no treatments or vaccines that had been shown to be safe and effective for treating or preventing EVD, limiting health care providers to offer supportive care under extremely challenging circumstances and at great risk to themselves. Over time, however, drugs and vaccines in the development pipeline were prioritized based on all available research data and were moved forward for evaluation in clinical trials to demonstrate safety and efficacy. The armamentarium against EVD eventually included biologics such as monoclonal antibodies, convalescent plasma, and vaccines as well as small molecule therapeutics such as small interfering RNAs and nucleoside analogs. This article provides a high-level overview of the interventions and prophylactics considered for use in the outbreak and discusses the challenges faced when attempting to deploy investigational countermeasures in the midst of an evolving epidemic.

Essentials of filoviral load quantification

Quantitative measurement of viral load is an important parameter in the management of filovirus disease outbreaks because viral load correlates with severity of disease, survival, and infectivity. During the ongoing Ebola virus disease outbreak in parts of Western Africa, most assays used in the detection of Ebola virus disease by more than 44 diagnostic laboratories yielded qualitative results. Regulatory hurdles involved in validating quantitative assays and the urgent need for a rapid Ebola virus disease diagnosis precluded development of validated quantitative assays during the outbreak. Because of sparse quantitative data obtained from these outbreaks, opportunities for study of correlations between patient outcome, changes in viral load during the course of an outbreak, disease course in asymptomatic individuals, and the potential for virus transmission between infected patients and contacts have been limited. We strongly urge the continued development of quantitative viral load assays to carefully evaluate these parameters in future outbreaks of filovirus disease.

The 2014–2015 Ebola outbreak in West Africa: Hands On

The International Consortium for Prevention and Infection Control (ICPIC) organises a biannual conference (ICPIC) on various subjects related to infection prevention, treatment and control. During ICPIC 2015, held in Geneva in June 2015, a full one-day session focused on the 2014–2015 Ebola virus disease (EVD) outbreak in West Africa. This article is a non-exhaustive compilation of these discussions. It concentrates on lessons learned and imagining a way forward for the communities most affected by the epidemic. The reader can access video recordings of all lectures delivered during this one-day session, as referenced. Topics include the timeline of the international response, linkages between the dynamics of the epidemic and infection prevention and control, the importance of community engagement, and updates on virology, diagnosis, treatment and vaccination issues. The paper also includes discussions from public health, infectious diseases, critical care and infection control experts who cared for patients with EVD in Africa, in Europe, and in the United Sates and were involved in Ebola preparedness in both high- and low-resource settings and countries. This review concludes that too little is known about the pathogenesis and treatment of EVD, therefore basic and applied research in this area are urgently required. Furthermore, it is clear that epidemic preparedness needs to improve globally, in particular through the strengthening of health systems at local and national levels. There is a strong need for culturally sensitive approaches to public health which could be designed and delivered by social scientists and medical professionals working together. As of December 2015, this epidemic killed more than 11,000 people and infected more than 28,000; it has also generated more than 17,000 survivors and orphans, many of whom face somatic and psychological complications. The continued treatment and rehabilitation of these people is a public health priority, which also requires an integration of specific medical and social science approaches, not always available in West Africa.

Sequelae of Ebola virus disease: the emergency within the emergency

As the massive outbreak of Ebola virus disease (EVD) in west Africa wanes, it has become increasingly clear that thousands of survivors have many sequelae, some of which might be very severe, such as arthritis and vision-threatening uveitis. The mental health effects of EVD on survivors and other family and community members is similarly profound. Furthermore, it is increasingly being recognised that Ebola virus might persist for weeks or months in selected body compartments of survivors, most notably in the semen of men, bringing risk of renewed transmission where it has previously been eliminated. These challenges to EVD survivors constitute a new emergency in terms of addressing individual patient need and to control the disease spread. In this Review, we assess what is known regarding the sequelae of EVD, including possible delayed virus clearance. We discuss some of the key challenges regarding the provision of care to survivors and implementation of necessary future research.

Experimental Treatment with Favipiravir for Ebola Virus Disease (the JIKI Trial): A Historically Controlled, Single-Arm Proof-of-Concept Trial in Guinea

BACKGROUND

Ebola virus disease (EVD) is a highly lethal condition for which no specific treatment has proven efficacy. In September 2014, while the Ebola outbreak was at its peak, the World Health Organization released a short list of drugs suitable for EVD research. Favipiravir, an antiviral developed for the treatment of severe influenza, was one of these. In late 2014, the conditions for starting a randomized Ebola trial were not fulfilled for two reasons. One was the perception that, given the high number of patients presenting simultaneously and the very high mortality rate of the disease, it was ethically unacceptable to allocate patients from within the same family or village to receive or not receive an experimental drug, using a randomization process impossible to understand by very sick patients. The other was that, in the context of rumors and distrust of Ebola treatment centers, using a randomized design at the outset might lead even more patients to refuse to seek care. Therefore, we chose to conduct a multicenter non-randomized trial, in which all patients would receive favipiravir along with standardized care. The objectives of the trial were to test the feasibility and acceptability of an emergency trial in the context of a large Ebola outbreak, and to collect data on the safety and effectiveness of favipiravir in reducing mortality and viral load in patients with EVD. The trial was not aimed at directly informing future guidelines on Ebola treatment but at quickly gathering standardized preliminary data to optimize the design of future studies.

METHODS AND FINDINGS

Inclusion criteria were positive Ebola virus reverse transcription PCR (RT-PCR) test, age ≥ 1 y, weight ≥ 10 kg, ability to take oral drugs, and informed consent. All participants received oral favipiravir (day 0: 6,000 mg; day 1 to day 9: 2,400 mg/d). Semi-quantitative Ebola virus RT-PCR (results expressed in "cycle threshold" [Ct]) and biochemistry tests were performed at day 0, day 2, day 4, end of symptoms, day 14, and day 30. Frozen samples were shipped to a reference biosafety level 4 laboratory for RNA viral load measurement using a quantitative reference technique (genome copies/milliliter). Outcomes were mortality, viral load evolution, and adverse events. The analysis was stratified by age and Ct value. A "target value" of mortality was defined a priori for each stratum, to guide the interpretation of interim and final analysis. Between 17 December 2014 and 8 April 2015, 126 patients were included, of whom 111 were analyzed (adults and adolescents, ≥13 y, n = 99; young children, ≤6 y, n = 12). Here we present the results obtained in the 99 adults and adolescents. Of these, 55 had a baseline Ct value ≥ 20 (Group A Ct ≥ 20), and 44 had a baseline Ct value < 20 (Group A Ct < 20). Ct values and RNA viral loads were well correlated, with Ct = 20 corresponding to RNA viral load = 7.7 log10 genome copies/ml. Mortality was 20% (95% CI 11.6%-32.4%) in Group A Ct ≥ 20 and 91% (95% CI 78.8%-91.1%) in Group A Ct < 20. Both mortality 95% CIs included the predefined target value (30% and 85%, respectively). Baseline serum creatinine was ≥110 μmol/l in 48% of patients in Group A Ct ≥ 20 (≥300 μmol/l in 14%) and in 90% of patients in Group A Ct < 20 (≥300 μmol/l in 44%). In Group A Ct ≥ 20, 17% of patients with baseline creatinine ≥110 μmol/l died, versus 97% in Group A Ct < 20. In patients who survived, the mean decrease in viral load was 0.33 log10 copies/ml per day of follow-up. RNA viral load values and mortality were not significantly different between adults starting favipiravir within <72 h of symptoms compared to others. Favipiravir was well tolerated.

CONCLUSIONS

In the context of an outbreak at its peak, with crowded care centers, randomizing patients to receive either standard care or standard care plus an experimental drug was not felt to be appropriate. We did a non-randomized trial. This trial reaches nuanced conclusions. On the one hand, we do not conclude on the efficacy of the drug, and our conclusions on tolerance, although encouraging, are not as firm as they could have been if we had used randomization. On the other hand, we learned about how to quickly set up and run an Ebola trial, in close relationship with the community and non-governmental organizations; we integrated research into care so that it improved care; and we generated knowledge on EVD that is useful to further research. Our data illustrate the frequency of renal dysfunction and the powerful prognostic value of low Ct values. They suggest that drug trials in EVD should systematically stratify analyses by baseline Ct value, as a surrogate of viral load. They also suggest that favipiravir monotherapy merits further study in patients with medium to high viremia, but not in those with very high viremia.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02329054.

Clinical Management of Ebola Virus Disease in the United States and Europe

BACKGROUND

Available data on the characteristics of patients with Ebola virus disease (EVD) and clinical management of EVD in settings outside West Africa, as well as the complications observed in those patients, are limited.

METHODS

We reviewed available clinical, laboratory, and virologic data from all patients with laboratory-confirmed Ebola virus infection who received care in U.S. and European hospitals from August 2014 through December 2015.

RESULTS

A total of 27 patients (median age, 36 years [range, 25 to 75]) with EVD received care; 19 patients (70%) were male, 9 of 26 patients (35%) had coexisting conditions, and 22 (81%) were health care personnel. Of the 27 patients, 24 (89%) were medically evacuated from West Africa or were exposed to and infected with Ebola virus in West Africa and had onset of illness and laboratory confirmation of Ebola virus infection in Europe or the United States, and 3 (11%) acquired EVD in the United States or Europe. At the onset of illness, the most common signs and symptoms were fatigue (20 patients [80%]) and fever or feverishness (17 patients [68%]). During the clinical course, the predominant findings included diarrhea, hypoalbuminemia, hyponatremia, hypokalemia, hypocalcemia, and hypomagnesemia; 14 patients (52%) had hypoxemia, and 9 (33%) had oliguria, of whom 5 had anuria. Aminotransferase levels peaked at a median of 9 days after the onset of illness. Nearly all the patients received intravenous fluids and electrolyte supplementation; 9 (33%) received noninvasive or invasive mechanical ventilation; 5 (19%) received continuous renal-replacement therapy; 22 (81%) received empirical antibiotics; and 23 (85%) received investigational therapies (19 [70%] received at least two experimental interventions). Ebola viral RNA levels in blood peaked at a median of 7 days after the onset of illness, and the median time from the onset of symptoms to clearance of viremia was 17.5 days. A total of 5 patients died, including 3 who had respiratory and renal failure, for a mortality of 18.5%.

CONCLUSIONS

Among the patients with EVD who were cared for in the United States or Europe, close monitoring and aggressive supportive care that included intravenous fluid hydration, correction of electrolyte abnormalities, nutritional support, and critical care management for respiratory and renal failure were needed; 81.5% of these patients who received this care survived.

Ebola virus disease diagnosis by real-time RT-PCR: A comparative study of 11 different procedures

BACKGROUND

The diagnosis of Ebola virus disease relies on the detection of viral RNA in blood by real-time reverse-transcription PCR. While several of these assays were developed during the unprecedented 2013-2015 Ebola virus disease outbreak in West Africa, few were applied in the field.

OBJECTIVES

To compare technical performances and practical aspects of 11 Ebola virus real-time reverse-transcription PCR procedures.

STUDY DESIGN

We selected the most promising assays using serial dilutions of culture-derived Ebola virus RNA and determined their analytical sensitivity and potential range of quantification using quantified in vitro transcribed RNA; viral load values in the serum of an Ebola virus disease patient obtained with these assays were reported. Finally, ease of use and turnaround times of these kits were evaluated.

RESULTS

Commercial assays were at least as sensitive as in-house tests. Five of the former (Altona, Roche, Fast-track Diagnostics, and Life Technologies) were selected for further evaluation. Despite differences in analytical sensitivity and limits of quantification, all of them were suitable for Ebola virus diagnosis and viral load estimation. The Lifetech Lyophilized Ebola Virus (Zaire 2014) assay (Life Technologies) appeared particularly promising, displaying the highest analytical sensitivity and shortest turnaround time, in addition to requiring no reagent freezing.

CONCLUSIONS

Commercial kits were at least as sensitive as in-house tests and potentially easier to use in the field than the latter. This qualitative comparison of real-time reverse transcription PCR assays may serve as a basis for the design of future Ebola virus disease diagnostics.

Risk factors for transmission of Ebola or Marburg virus disease: a systematic review and meta-analysis

BACKGROUND

The Ebola virus disease outbreak that started in Western Africa in 2013 was unprecedented because it spread within densely populated urban environments and affected many thousands of people. As a result, previous advice and guidelines need to be critically reviewed, especially with regard to transmission risks in different contexts.

METHODS

Scientific and grey literature were searched for articles about any African filovirus. Articles were screened for information about transmission (prevalence or odds ratios especially). Data were extracted from eligible articles and summarized narratively with partial meta-analysis. Study quality was also evaluated.

RESULTS

A total of 31 reports were selected from 6552 found in the initial search. Eight papers gave numerical odds for contracting filovirus illness; 23 further articles provided supporting anecdotal observations about how transmission probably occurred for individuals. Many forms of contact (conversation, sharing a meal, sharing a bed, direct or indirect touching) were unlikely to result in disease transmission during incubation or early illness. Among household contacts who reported directly touching a case, the attack rate was 32% [95% confidence interval (CI) 26-38%]. Risk of disease transmission between household members without direct contact was low (1%; 95% CI 0-5%). Caring for a case in the community, especially until death, and participation in traditional funeral rites were strongly associated with acquiring disease, probably due to a high degree of direct physical contact with case or cadaver.

CONCLUSIONS

Transmission of filovirus is unlikely except through close contact, especially during the most severe stages of acute illness. More data are needed about the context, intimacy and timing of contact required to raise the odds of disease transmission. Risk factors specific to urban settings may need to be determined.

Presence and Persistence of Ebola or Marburg Virus in Patients and Survivors: A Rapid Systematic Review

BACKGROUND

The 2013-15 Ebola outbreak was unprecedented due to sustained transmission within urban environments and thousands of survivors. In 2014 the World Health Organization stated that there was insufficient evidence to give definitive guidance about which body fluids are infectious and when they pose a risk to humans. We report a rapid systematic review of published evidence on the presence of filoviruses in body fluids of infected people and survivors.

METHODS

Scientific articles were screened for information about filovirus in human body fluids. The aim was to find primary data that suggested high likelihood of actively infectious filovirus in human body fluids (viral RNA). Eligible infections were from Marburg virus (MARV or RAVV) and Zaire, Sudan, Taï Forest and Bundibugyo species of Ebola. Cause of infection had to be laboratory confirmed (in practice either tissue culture or RT-PCR tests), or evidenced by compatible clinical history with subsequent positivity for filovirus antibodies or inflammatory factors. Data were extracted and summarized narratively.

RESULTS

6831 unique articles were found, and after screening, 33 studies were eligible. For most body fluid types there were insufficient patients to draw strong conclusions, and prevalence of positivity was highly variable. Body fluids taken >16 days after onset were usually negative. In the six studies that used both assay methods RT-PCR tests for filovirus RNA gave positive results about 4 times more often than tissue culture.

CONCLUSIONS

Filovirus was reported in most types of body fluid, but not in every sample from every otherwise confirmed patient. Apart from semen, most non-blood, RT-PCR positive samples are likely to be culture negative and so possibly of low infectious risk. Nevertheless, it is not apparent how relatively infectious many body fluids are during or after illness, even when culture-positive, not least because most test results come from more severe cases. Contact with blood and blood-stained body fluids remains the major risk for disease transmission because of the known high viral loads in blood.

[Ebola virus disease: Update]

The first known Ebola outbreak occurred in 1976. Since then, 24 limited outbreaks had been reported in Central Africa, but never affecting more than 425 persons. The current outbreak in Western Africa is the largest in history with 28,220 reported cases and 11,291 deaths. The magnitude of the epidemic has caused worldwide alarm. For the first time, evacuated patients were treated outside Africa, and secondary cases have occurred in Spain and the United States. Since the start of the current epidemic, our knowledge about the epidemiology, clinical picture, laboratory findings, and virology of Ebola virus disease has considerably expanded. For the first time, experimental treatment has been tried, and there have been spectacular advances in vaccine development. A review is presented of these advances in the knowledge of Ebola virus disease.

Low-dose ribavirin potentiates the antiviral activity of favipiravir against hemorrhagic fever viruses

Favipiravir is approved in Japan to treat novel or re-emerging influenza viruses, and is active against a broad spectrum of RNA viruses, including Ebola. Ribavirin is the only other licensed drug with activity against multiple RNA viruses. Recent studies show that ribavirin and favipiravir act synergistically to inhibit bunyavirus infections in cultured cells and laboratory mice, likely due to their different mechanisms of action. Convalescent immune globulin is the only approved treatment for Argentine hemorrhagic fever caused by the rodent-borne Junin arenavirus. We previously reported that favipiravir is highly effective in a number of small animal models of Argentine hemorrhagic fever. We now report that addition of low dose of ribavirin synergistically potentiates the activity of favipiravir against Junin virus infection of guinea pigs and another arenavirus, Pichinde virus infection of hamsters. This suggests that the efficacy of favipiravir against hemorrhagic fever viruses can be further enhanced through the addition of low-dose ribavirin.