An Assessment of Anesthesia Capacity in Liberia: Opportunities for Rebuilding Post-Ebola.

BACKGROUND: The health system of Liberia, a low-income country in West Africa, was devastated by a civil war lasting from 1989 to 2003. Gains made in the post-war period were compromised by the 2014-2016 Ebola epidemic. The already fragile health system experienced worsening of health indicators, including an estimated 111% increase in the country's maternal mortality rate post-Ebola. Access to safe surgery is necessary for improvement of these metrics, yet data on surgical and anesthesia capacity in Liberia post-Ebola are sparse. The aim of this study was to describe anesthesia capacity in Liberia post-Ebola as part of the development of a National Surgical, Obstetric, and Anesthesia Plan (NSOAP). METHODS: Using the World Federation of Societies of Anaesthesiologists (WFSA) Anaesthesia Facility Assessment Tool (AFAT), we conducted a cross-sectional survey of 26 of 32 Ministry of Health recognized hospitals that provide surgical care in Liberia. The surveyed hospitals served approximately 90% of the Liberian population. This assessment surveyed infrastructure, workforce, service delivery, information management, medications, and equipment and was performed between July and September 2019. Researchers obtained data from interviews with anesthesia department heads, medical directors and through direct site visits where possible. RESULTS: Anesthesiologist and nurse anesthetist workforce densities were 0.02 and 1.56 per 100,000 population, respectively, compared to 0.63 surgeons per 100,000 population and 0.52 obstetricians/gynecologists per 100,000 population. On average, there were 2 functioning operating rooms (ORs; OR in working condition that can be used for patient care) per hospital (standard deviation [SD] = 0.79; range, 1-3). Half of the hospitals surveyed had a postanesthesia care unit (PACU) and intensive care unit (ICU); however, only 1 hospital had mechanical ventilation capacity in the ICU. Ketamine and lidocaine were widely available. Intravenous (IV) morphine was always available in only 6 hospitals. None of the hospitals surveyed completely met the minimum World Health Organization (WHO)-WFSA standards for health care facilities where surgery and anesthesia are provided. CONCLUSIONS: Overall, we noted several critical gaps in anesthesia and surgical capacity in Liberia, in spite of the massive global response post-Ebola directed toward health system development. Further investment across all domains is necessary to attain minimum international standards and to facilitate the provision of safe surgery and anesthesia in Liberia. The study results will be considered in development of an NSOAP for Liberia.

Immunotherapeutic strategies to target vulnerabilities in the Ebolavirus glycoprotein.

The 2014 Ebola virus disease (EVD) outbreak in West Africa and the subsequent outbreaks of 2018-2020 in Equator and North Kivu provinces of the Democratic Republic of the Congo illustrate the public health challenges of emerging and reemerging viruses. EVD has a high case fatality rate with a rapidly progressing syndrome of fever, rash, vomiting, diarrhea, and bleeding diathesis. Recently, two monoclonal-antibody-based therapies received United States Food and Drug Administration (FDA) approval, and there are several other passive immunotherapies that hold promise as therapeutics against other species of Ebolavirus. Here, we review concepts needed to understand mechanisms of action, present an expanded schema to define additional sites of vulnerability on the viral glycoprotein, and review current antibody-based therapeutics. The concepts described are used to gain insights into the key characteristics that represent functional targets for immunotherapies against Zaire Ebolavirus and other emerging viruses within the Ebolavirus genus.

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

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). At day 13 of clinical illness, a marked increase in antibody titers to most EBOV proteins and affinity maturation to GP is associated with rapid decline in viral replication and illness severity. At one year, despite undetectable virus, a diverse IgM repertoire against VP40 and GP epitopes is observed suggesting occult viral persistence. Rabbit immunization experiments identify key immunodominant sites of GP, while challenge studies in mice found these epitopes induce EBOV-neutralizing antibodies and protect against lethal EBOV challenge. This study reveals markers of viral persistence and provides promising approaches for development and evaluation of vaccines and therapeutics.

Development and characterization of two GP-specific monoclonal antibodies, which synergistically protect non-human primates against Ebola lethal infection.

Ebola fever is an acute highly contagious viral disease characterized by severe course, high mortality and development of hemorrhagic syndrome (tendency to skin hemorrhage and bleeding of mucous membranes). The mortality rate of the disease 60-90%. Nowadays, there are no licensed specific therapeutic agents for Ebola in the world. Monoclonal antibodies (MAbs) having viral neutralizing activity with high specificity to the GP protein of the Ebola virus are considered as candidate highly effective antiviral drugs. In our study, for the first time a panel of mouse monoclonal antibodies specifically binding to EBOV GP protein was obtained using recombinant human adenovirus 5 serotype, expressing GP protein (Ad5-GP). The virus-neutralizing capacities of antibodies were evaluated on the Ebola virus cell infection model, as well as recombinant vesicular stomatitis virus pseudotyped by GP Ebola virus protein (rVSV-GP) cell infection model. Based on the results of virus neutralization, two most promising clones were selected, the specific and protective capacities of which were determined. The study of the protection of selected individual antibody clones, as well as their combinations on the model of lethal infection of rhesus macaques with Ebola virus showed that intravenous administration of a mixture of antibodies in the amount of 50 mg/kg 24 h after infection leads to the survival of 100% of the animals, while individual clones of antibodies possess partial protection (0-30%). The results of the study suggest the important role of antibodies in controlling replication of the Ebola virus in vivo and show the possibility of using a mixture of antibodies specific to the GP to protect against lethal infection with the Ebola virus in the post-infected mode of administration.

Therapeutic Monoclonal Antibodies for Ebola Virus Infection Derived from Vaccinated Humans.

We describe therapeutic monoclonal antibodies isolated from human volunteers vaccinated with recombinant adenovirus expressing Ebola virus glycoprotein (EBOV GP) and boosted with modified vaccinia virus Ankara. Among 82 antibodies isolated from peripheral blood B cells, almost half neutralized GP pseudotyped influenza virus. The antibody response was diverse in gene usage and epitope recognition. Although close to germline in sequence, neutralizing antibodies with binding affinities in the nano- to pico-molar range, similar to "affinity matured" antibodies from convalescent donors, were found. They recognized the mucin-like domain, glycan cap, receptor binding region, and the base of the glycoprotein. A cross-reactive cocktail of four antibodies, targeting the latter three non-overlapping epitopes, given on day 3 of EBOV infection, completely protected guinea pigs. This study highlights the value of experimental vaccine trials as a rich source of therapeutic human monoclonal antibodies.

Priorities, Barriers, and Facilitators towards International Guidelines for the Delivery of Supportive Clinical Care during an Ebola Outbreak: A Cross-Sectional Survey.

During the Ebola outbreak, mortality reduction was attributed to multiple improvements in supportive care delivered in Ebola treatment units (ETUs). We aimed to identify high-priority supportive care measures, as well as perceived barriers and facilitators to their implementation, for patients with Ebola Virus Disease (EVD). We conducted a cross-sectional survey of key stakeholders involved in the response to the 2014⁻2016 West African EVD outbreak. Out of 57 email invitations, 44 responses were received, and 29 respondents completed the survey. The respondents listed insufficient numbers of health workers (23/29, 79%), improper tools for the documentation of clinical data (n = 22/28, 79%), insufficient material resources (n = 22/29, 76%), and unadapted personal protective equipment (n = 20/28, 71%) as the main barriers to the provision of supportive care in ETUs. Facilitators to the provision of supportive care included team camaraderie (n in agreement = 25/28, 89%), ability to speak the local language (22/28, 79%), and having treatment protocols in place (22/28, 79%). This survey highlights a consensus across various stakeholders involved in the response to the 2014⁻2016 EVD outbreak on a limited number of high-priority supportive care interventions for clinical practice guidelines. Identified barriers and facilitators further inform the application of guidelines.

Antibody-Dependent Enhancement of Ebola Virus Infection by Human Antibodies Isolated from Survivors.

Some monoclonal antibodies (mAbs) recovered from survivors of filovirus infections can protect against infection. It is currently unknown whether natural infection also induces some antibodies with the capacity for antibody-dependent enhancement (ADE). A panel of mAbs obtained from human survivors of filovirus infection caused by Ebola, Bundibugyo, or Marburg viruses was evaluated for their ability to facilitate ADE. ADE was observed readily with all mAbs examined at sub-neutralizing concentrations, and this effect was not restricted to mAbs with a particular epitope specificity, neutralizing capacity, or subclass. Blocking of specific Fcγ receptors reduced but did not abolish ADE that was associated with high-affinity binding antibodies, suggesting that lower-affinity interactions still cause ADE. Mutations of Fc fragments of an mAb that altered its interaction with Fc receptors rendered the antibody partially protective in vivo at a low dose, suggesting that ADE counteracts antibody-mediated protection and facilitates dissemination of filovirus infections.

Immunogenicity of a Candidate Ebola Hemorrhagic Fever Vaccine in Mice Based on Controlled In Vitro Expression of Ebolavirus Glycoprotein.

Ebolavirus (EBOV) is the etiology of Ebola hemorrhagic fever (EHF). A major EHF outbreak in 2014-2015 in West Africa claimed >11,000 lives. A licensed vaccine is not available for EHF, although several vaccines have undergone clinical trials. We developed a human adenovirus (Ad) serotype 5-based candidate EHF vaccine based on controlled expression of the EBOV (Makona strain) glycoprotein (GP) as the immunogen. Two clones, AdGP72 and AdGP75, and a control Ad515 vector, were generated and tested for protein expression in vitro and immunogenicity in mice. Eight groups of mice were immunized with three doses of buffer, Ad515, AdGP72, and AdGP75, by two different dose regimens. Three different antigens (AdGP75-infected Vero E6 cell extract and two baculovirus expressed EBOV GP antigens, namely, GP alone or GP with EBOV VP40) were used to evaluate the immune response. Expression studies indicated that full-length GP was cleaved into its component subunits when expressed in mammalian cells through the Ad vectors. Moreover, in coimmunoprecipitation studies, EBOV GP was found to be associated with VP40 when expressed in baculoviruses. The candidate vaccines were immunogenic in mice, as evaluated by enzyme-linked immunosorbent assay using mammalian- or baculovirus-derived antigens. Further characterization and development of the candidate vaccines are warranted.

Enhanced case management can be delivered for patients with EVD in Africa: Experience from a UK military Ebola treatment centre in Sierra Leone.

BACKGROUND: Limited data exist describing supportive care management, laboratory abnormalities and outcomes in patients with Ebola virus disease (EVD) in West Africa. We report data which constitute the first description of the provision of enhanced EVD case management protocols in a West African setting. METHODS: Demographic, clinical and laboratory data were collected by retrospective review of clinical and laboratory records of patients with confirmed EVD admitted between 5 November 2014 and 30 June 2015. RESULTS: A total of 44 EVD patients were admitted (median age 37 years (range 17-63), 32/44 healthcare workers), and excluding those evacuated, the case fatality rate was 49% (95% CI 33%-65%). No pregnant women were admitted. At admission 9/44 had stage 1 disease (fever and constitutional symptoms only), 12/44 had stage 2 disease (presence of diarrhoea and/or vomiting) and 23/44 had stage 3 disease (presence of diarrhoea and/or vomiting with organ failure), with case fatality rates of 11% (95% CI 1%-58%), 27% (95% CI 6%-61%), and 70% (95% CI 47%-87%) respectively (p = 0.009). Haemorrhage occurred in 17/41 (41%) patients. The majority (21/40) of patients had hypokalaemia with hyperkalaemia occurring in 12/40 patients. Acute kidney injury (AKI) occurred in 20/40 patients, with 14/20 (70%, 95% CI 46%-88%) dying, compared to 5/20 (25%, 95% CI 9%-49%) dying who did not have AKI (p = 0.01). Ebola virus (EBOV) PCR cycle threshold value at baseline was mean 20.3 (SD 4.3) in fatal cases and 24.8 (SD 5.5) in survivors (p = 0.007). Mean national early warning score (NEWS) at admission was 5.5 (SD 4.4) in fatal cases and 3.0 (SD 1.9) in survivors (p = 0.02). Central venous catheters were placed in 37/41 patients and intravenous fluid administered to 40/41 patients (median duration of 5 days). Faecal management systems were inserted in 21/41 patients, urinary catheters placed in 27/41 and blood component therapy administered to 20/41 patients. CONCLUSIONS: EVD is commonly associated life-threatening electrolyte imbalance and organ dysfunction. We believe that the enhanced levels of protocolized care, scale and range of medical interventions we report, offer a blueprint for the future management of EVD in resource-limited settings.

Selection, characterization, and thermal stabilization of llama single domain antibodies towards Ebola virus glycoprotein.

BACKGROUND: A key advantage of recombinant antibody technology is the ability to optimize and tailor reagents. Single domain antibodies (sdAbs), the recombinantly produced variable domains derived from camelid and shark heavy chain antibodies, provide advantages of stability and solubility and can be further engineered to enhance their properties. In this study, we generated sdAbs specific for Ebola virus envelope glycoprotein (GP) and increased their stability to expand their utility for use in austere locals. Ebola virus is extremely virulent and causes fatal hemorrhagic fever in ~ 50 percent of the cases. The viral GP binds to host cell receptors to facilitate viral entry and thus plays a critical role in pathogenicity. RESULTS: An immune phage display library containing more than 107 unique clones was developed from a llama immunized with a combination of killed Ebola virus and recombinantly produced GP. We panned the library to obtain GP binding sdAbs and isolated sdAbs from 5 distinct sequence families. Three GP binders with dissociation constants ranging from ~ 2 to 20 nM, and melting temperatures from ~ 57 to 72 °C were selected for protein engineering in order to increase their stability through a combination of consensus sequence mutagenesis and the addition of a non-canonical disulfide bond. These changes served to increase the melting temperatures of the sdAbs by 15-17 °C. In addition, fusion of a short positively charged tail to the C-terminus which provided ideal sites for the chemical modification of these sdAbs resulted in improved limits of detection of GP and Ebola virus like particles while serving as tracer antibodies. CONCLUSIONS: SdAbs specific for Ebola GP were selected and their stability and functionality were improved utilizing protein engineering. Thermal stability of antibody reagents may be of particular importance when operating in austere locations that lack reliable refrigeration. Future efforts can evaluate the potential of these isolated sdAbs as candidates for diagnostic or therapeutic applications for Ebola.

Clinical development of a recombinant Ebola vaccine in the midst of an unprecedented epidemic.

The 2014-2016 Ebola outbreak caused over 28,000 cases and 11,000 deaths. Merck & Co. Inc., Kenilworth, NJ USA and NewLink Genetics are working with private and public partners to develop and license an Ebola vaccine that was evaluated extensively during the outbreak. The vaccine referred to as V920 is a recombinant vesicular stomatitis virus (rVSV) in which the VSV-G envelope glycoprotein (GP) is completely replaced by the Zaire ebolavirus GP (rVSVΔG-ZEBOV-GP). Eight Phase I and four Phase II/III clinical trials enrolling approximately 17,000 subjects were conducted in parallel to the outbreak to assess the safety, immunogenicity, and/or efficacy of V920. Immunogenicity data demonstrate that anti-GP antibodies are generally detectable by ELISA by 14days postvaccination with up to 100% seroconversion observed by 28days post dose. In addition, the results of a ring vaccination trial conducted by the WHO and their partners in Guinea suggest robust vaccine efficacy within 10days of receipt of a single dose of vaccine. The vaccine is generally well-tolerated when administered to healthy, non-pregnant adults. The development of this vaccine candidate in the context of this unprecedented epidemic has involved the close cooperation of large number of international partners and highlights what we as a public health community can accomplish when working together towards a common goal. Study identification: V920-001 to V920-012. CLINICALTRIALS.GOV identifiers: NCT02269423; NCT02280408; NCT02374385; NCT02314923; NCT02287480; NCT02283099; NCT02296983; NCT02344407; NCT02378753; NCT02503202.

First Newborn Baby to Receive Experimental Therapies Survives Ebola Virus Disease.

A neonate born to an Ebola virus-positive woman was diagnosed with Ebola virus infection on her first day of life. The patient was treated with monoclonal antibodies (ZMapp), a buffy coat transfusion from an Ebola survivor, and the broad-spectrum antiviral GS-5734. On day 20, a venous blood specimen tested negative for Ebola virus by quantitative reverse-transcription polymerase chain reaction. The patient was discharged in good health on day 33 of life. Further follow-up consultations showed age-appropriate weight gain and neurodevelopment at the age of 12 months. This patient is the first neonate documented to have survived congenital infection with Ebola virus.

Apheresis for collection of Ebola convalescent plasma in Liberia.

PURPOSE: This report describes initiation of apheresis capability in Liberia, Africa to support a clinical trial of convalescent plasma therapy for Ebola Virus Disease. METHODS: A bloodmobile was outfitted in the United States as a four-bed apheresis unit with capabilities including pathogen reduction, electronic blood establishment computer system, designated areas for donor counseling and laboratory testing, and onboard electrical power generation. After air transport to Liberia, the bloodmobile was positioned at ELWA Hospital, Monrovia, and connected to the hospital's power grid. Liberian staff were trained to conduct donor screening, which included questionnaire and onsite blood typing and transfusion transmitted infection (TTI) testing, and plasma collection and processing. RESULTS: The bloodmobile was operational within 3 weeks after arrival of the advance team. Of 101 donors who passed the pre-screening questionnaire, 32 were deferred. Twenty-eight of ninty-nine tested survivors were deferred for positive transfusion transmitted infection (TTI) tests; twenty-one were positive for hepatitis B, hepatitis C, or human immunodeficiency virus. The majority of donors had type O blood; all but one were Rh positive. Forty-three survivors donated at least once; eighty-nine apheresis attempts resulted in eighty-one successful collections. CONCLUSIONS: Apheresis capability was emergently established in Liberia to support an efficacy trial of Ebola Convalescent Plasma. Extensive cooperation among multinational team members, engineers, logisticians, and blood safety technical personnel at the operational site was required to surmount challenges to execution posed by logistical factors. The high proportion of positive TTI tests supported the use of a pathogen reduction system to enhance product safety. J. Clin. Apheresis 32:175-181, 2017. © 2016 Wiley Periodicals, Inc.

Deployment of the 1st Area Medical Laboratory in a Split-Based Configuration During the Largest Ebola Outbreak in History.

BACKGROUND: The U.S. Army 1st Area Medical Laboratory (1st AML) is currently the only deployable medical CBRNE (Chemical, Biological, Radiological, Nuclear, and Explosives) laboratory in the Army's Forces Command. In support of the United States Agency for International Development Ebola response, the U.S. military initiated Operation United Assistance (OUA), and deployed approximately 2,500 service members to support the Government of Liberia's Ebola control efforts. Due to its unique molecular diagnostic and expeditionary capabilities, the 1st AML was ordered to deploy in October of 2014 in support of OUA via establishment of Ebola testing laboratories. To meet the unique mission requirements of OUA, the unit was re-organized to operate in a split-based configuration and sustain four separate Ebola testing laboratories. METHODS: This article is a review of the 1st AML's OUA participation in a split-based configuration. Topics highlighted include pre-deployment planning/training, operational/logistical considerations in fielding/withdrawing laboratories, laboratory testing results, disease and non-battle injuries, and lessons learned. FINDINGS: Fielding the 1st AML in a split-based configuration required careful pre-deployment planning, additional training, optimal use of personnel, and the acquisition of additional laboratory equipment. Challenges in establishing and sustaining remote laboratories in Liberia included: difficulties in transportation of equipment due to poor road infrastructure, heavy equipment unloading, and equipment damage during transit. Between November 26, 2014 and February 18, 2015 the four 1st AML labs successfully tested blood samples from patients and oral swabs collected by burial teams in rural Liberia. The most significant equipment malfunction during laboratory operations was generators powering the labs, with the same problem impacting headquarters. Generator failures delayed laboratory operations/result reporting, and put temperature sensitive reagents at risk. None of the 22 1st AML soldiers (at remote labs or headquarters) had an Ebola exposure, none were infected with malaria or other tropical diseases, and none required evacuation from the time deployed to remote sites. The primary medical condition encountered was acute gastroenteritis, and within the first week of arrival to Liberia, 19 (86%) soldiers were affected. DISCUSSION/IMPACT/RECOMMENDATIONS: With proper planning and training, the 1st AML can successfully conduct split-based operations in an outbreak setting, and this capability can be utilized in future operations. The performance of the 1st AML during the current Ebola outbreak highlights the value of this asset, and the need to continue its evolution to support U.S. military operations.

Ebola virus – from neglected threat to global emergency state / Vírus ébola – de ameaça negligenciada ao estado de emergência global

SUMMARY Objective: This review aims to update knowledge about Ebola virus disease (EVD) and recent advances in its diagnosis, treatment and prevention. Method: A literature review was performed using the following databases: ISI Web of Knowledge, PubMed, IRIS, Scopus and the websites of the CDC and the WHO. Additionally, we have included articles and reports referenced in the basic literature search, and news that were considered relevant. Results: The Ebola virus, endemic in some parts of Africa, is responsible for a severe form of hemorrhagic fever in humans; bats are probably its natural reservoir. It is an extremely virulent virus and easily transmitted by bodily fluids. EVD's complex pathophysiology, characterized by immunosuppression as well as stimulation of an intense inflammatory response, results in a syndrome similar to septic shock. The diagnosis is difficult due to the initial symptoms that mimic other diseases. Despite the high mortality rates that can amount to 90%, a prophylaxis (chemical or vaccine) or effective treatment does not exist. Two vaccines and experimental therapies are being developed for the prevention and treatment of EVD. Conclusion: Although the virus is known for about 40 years, the lack of knowledge obtained and the disinterest of government authorities in the countries involved justify the state of emergency currently exists regarding this infectious agent. Only the coordination of multiple entities and the effective commitment of the international community will facilitate the control and effective prevention of EVD.

RESUMO Objetivo: esta revisão tem como objetivo atualizar os conhecimentos sobre a doença do vírus ébola (DVE) e sobre os recentes avanços nos métodos de diagnóstico, tratamento e prevenção. Método: foi realizada uma revisão de literatura, utilizando as seguintes bases de dados: ISI Web of Knowledge, PubMed, IRIS, Scopus e os sites do Centers for Disease Control and Prevention (CDC) e da Organização Mundial da Saúde (OMS). Adicionalmente, foram incluídos artigos e relatórios referenciados na pesquisa bibliográfica de base e notícias consideradas relevantes. Resultados: o vírus ébola, endêmico de algumas regiões da África, é responsável por uma forma grave de febre hemorrágica no homem, e os morcegos são provavelmente o seu reservatório natural. É um vírus extremamente virulento e de fácil transmissão pelos fluidos corporais. A complexa fisiopatologia da doença, caracterizada pela imunossupressão e pelo estímulo a uma intensa resposta inflamatória, resulta em uma síndrome semelhante ao choque séptico. O seu diagnóstico é difícil, por causa da sintomatologia inicial, que mimetiza outras doenças. Apesar das altas taxas de mortalidade, que podem alcançar os 90%, não existe profilaxia (química ou vacinal) ou tratamento eficaz. Encontram-se em desenvolvimento duas vacinas e terapias experimentais para a prevenção e o tratamento da DVE. Conclusão: apesar de ser um vírus conhecido há cerca de 40 anos, o escasso conhecimento obtido e o desinteresse das entidades governamentais de países envolvidos justificam o estado de emergência que se vive atualmente em relação a esse agente infeccioso. A coordenação por múltiplas entidades e o empenho efetivo da comunidade internacional facilitarão o seu controle e a prevenção eficaz.

A "Trojan horse" bispecific-antibody strategy for broad protection against ebolaviruses.

There is an urgent need for monoclonal antibody (mAb) therapies that broadly protect against Ebola virus and other filoviruses. The conserved, essential interaction between the filovirus glycoprotein, GP, and its entry receptor Niemann-Pick C1 (NPC1) provides an attractive target for such mAbs but is shielded by multiple mechanisms, including physical sequestration in late endosomes. Here, we describe a bispecific-antibody strategy to target this interaction, in which mAbs specific for NPC1 or the GP receptor-binding site are coupled to a mAb against a conserved, surface-exposed GP epitope. Bispecific antibodies, but not parent mAbs, neutralized all known ebolaviruses by coopting viral particles themselves for endosomal delivery and conferred postexposure protection against multiple ebolaviruses in mice. Such "Trojan horse" bispecific antibodies have potential as broad antifilovirus immunotherapeutics.