Ebola Vaccine Research Articles

“Let’s say it wears an Ebola Coat, but it’s not Ebola”: The Rhetoric and Politics of Reframing a Vaccine for a Transnational Clinical Trial

Focusing on how disease, health and vaccine research take on different forms, meanings and interpretations in diverse contexts, we examine the use of rhetoric to recruit people living with HIV in sub-Saharan Africa for an Ebola vaccine clinical trial. Conducted after the West African Ebola outbreak in a country that had not been affected by Ebola, the urgency, relevance and materiality of disease, health and biomedical research takes on different shapes, meanings and understandings. The limitations of multilateral initiatives to address inequalities in associated healthcare and access to essential medicines and vaccines highlight the tensions created when neither local researchers nor patient communities have been involved in the design or planning of the trial, and when the pathologies targeted by experimental technologies are either inappropriate for the people they are aimed at, or unfold without the knowledge of a social consensus. By deciphering the metaphorical discourse on an Ebola vaccine candidate and the erasure of a viral ontology from the hybrid technology to which it gives rise, we understand that the discourse of clinic staff makes it possible to establish a scientific truth in the service of instrumental productivity: manufacturing consent and recruiting arms for vaccine shots. In this article, we show that the closure of biomedicine to an esoteric discourse reflects the weakness of science in communicating what it actually does and the techniques it produces. It also addresses the failure of community engagement in the field of emerging infectious diseases.

Development of Long-Term Stability of Enveloped rVSV Viral Vector Expressing SARS-CoV-2 Antigen Using a DOE-Guided Approach

Liquid formulations have been successfully used in many viral vector vaccines including influenza (Flu), hepatitis B, polio (IPV), Ebola, and COVID-19 vaccines. The main advantage of liquid formulations over lyophilized formulations is that they are cost-effective, as well as easier to manufacture and distribute. However, studies have shown that the liquid formulations of enveloped viral vector vaccines are not stable over extended periods of time. In this study, we explored the development of the liquid formulations of an enveloped recombinant Vesicular Stomatitis Virus (VSV) expressing the SARS-CoV-2 spike glycoprotein. To do so, we used a design of experiments (DOE) method, which allowed us to assess the stability dynamics of the viral vector in an effective manner. An initial stability study showed that trehalose, gelatin, and histidine were effective at maintaining functional viral titers during freeze–thaw stress and at different temperatures (−20, 4, 20, and 37 °C). These preliminary data helped to identify critical factors for the subsequent implementation of the DOE method that incorporated a stress condition at 37 °C. We used the DOE results to identify the optimal liquid formulations under the selected accelerated stress conditions, which then guided the identification of long-term storage conditions for further evaluation. In the long-term stability study, we identified several liquid formulations made of sugar (sucrose, trehalose, and sorbitol), gelatin, and a histidine buffer that resulted in the improved stability of rVSV-SARS-CoV-2 at 4 °C for six months. This study highlights an effective approach for the development of liquid formulations for viral vector vaccines, contributing significantly to the existing knowledge on enveloped viral vector thermostability.

Machine Learning Analysis of Radio Data to Uncover Community Perceptions on the Ebola Outbreak in Uganda

Radio is vital for people, especially in rural areas, to share their concerns through interactive talk shows. Understanding public perceptions of pandemics is crucial because they influence people’s attitudes and health-seeking behaviors. This study used machine learning to analyze English and Luganda radio broadcast data to understand public perceptions and perspectives on the Ebola outbreak in Uganda. Our findings revealed three main speaker categories: media personalities, community guests and listeners, and government officials. The government made the most significant effort to educate the public about the Ebola outbreak. The analysis showed that the community was hesitant to use Ebola vaccines, believing that they had not been tested on other populations where the Ebola virus had originated. The community was also concerned about the effects of the lockdown measures imposed during the COVID-19 pandemic. The analysis of the radio broadcast data revealed differences in the timing and content of the conversations between male and female speakers. These experiences can inform population-specific policies for handling ongoing and future pandemics.

Replication, safety and immunogenicity of the vectored Ebola vaccine rVSV-ΔG-ZEBOV-GP in a sub-Saharan African paediatric population: A randomised controlled, open-label trial in children aged 1-12 years living in Lambaréné, Gabon

Unlike adults, children experienced stronger and longer vector replication in plasma and shedding in saliva following rVSVΔG-ZEBOV-GP vaccination. The resulting risks of immunosuppression or immune hyperactivation leading to increased Adverse Events (AEs) and altered antibody responses are concerns that have been addressed in the present manuscript. Children aged 1-12 years living in Gabon received either rVSVΔG-ZEBOV-GP (ERVEBO®) vaccine or the varicella-zoster virus (VZV) vaccine (VZV). The concentration of rVSVΔG vector in blood and saliva, the occurrence of AEs up to day 28; the anti-rVSVΔG-ZEBOV-GP and anti-VZV IgG antibody titres, neutralising and avidity functions of anti-rVSVΔG-ZEBOV-GP by day 365; were assessed in serum. (PACTR202005733552021) FINDINGS: In the rVSVΔG-ZEBOV-GP group, 70% and 7% of children had >0 copies/ml of rVSVΔG respectively in plasma by day 3 and in saliva by day 14 after vaccination, with no detection on day 28. Significantly higher but transient AEs occurred in the rVSVΔG-ZEBOV-GP group. Both vaccines induced seroconversion on day 28 and sustainable IgG antibody titres by day 365. Avidity and neutralisation functions of the anti-rVSVΔG-ZEBOV-GP antibodies peaked at day 28 and were maintained by day 365. The replication and shedding do not affect the favourable risk-benefit balance of the rVSVΔG-ZEBOV-GP in children.

Immunogenicity of an Extended Dose Interval for the Ad26.ZEBOV, MVA-BN-Filo Ebola Vaccine Regimen in Adults and Children in the Democratic Republic of the Congo.

During the 2018-2020 Ebola virus disease outbreak in Democratic Republic of the Congo, a phase 3 trial of the Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine (DRC-EB-001) commenced in Goma, with participants being offered the two-dose regimen given 56 days apart. Suspension of trial activities in 2020 due to the COVID-19 pandemic led to some participants receiving a late dose 2 outside the planned interval. Blood samples were collected from adults, adolescents, and children prior to their delayed dose 2 vaccination and 21 days after, and tested for IgG binding antibodies against Ebola virus glycoprotein using the Filovirus Animal Nonclinical Group (FANG) ELISA. Results from 133 participants showed a median two-dose interval of 9.3 months. The pre-dose 2 antibody geometric mean concentration (GMC) was 217 ELISA Units (EU)/mL (95% CI 157; 301) in adults, 378 EU/mL (281; 510) in adolescents, and 558 EU/mL (471; 661) in children. At 21 days post-dose 2, the GMC increased to 22,194 EU/mL (16,726; 29,449) in adults, 37,896 EU/mL (29,985; 47,893) in adolescents, and 34,652 EU/mL (27,906; 43,028) in children. Participants receiving a delayed dose 2 had a higher GMC at 21 days post-dose 2 than those who received a standard 56-day regimen in other African trials, but similar to those who received the regimen with an extended interval.

Innate and cellular immune response to the Ebola vaccine Ad26.ZEBOV, MVA-BN-Filo: an ancillary study of the EBL2001 phase II trial.

The EBL2001 phase 2 trial tested the two-dose Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine in Europe. Safety and humoral immunogenicity assessments led to EU market authorization in 2020. Complementary analyses of immune responses are warranted to better characterize vaccine effects. We conducted an ancillary study to analyze changes in the serum and cellular responses. Serum biomarkers of activation/inflammation were evaluated using a Luminex assay. Vaccine-elicited T cell responses and functions were evaluated assessing their phenotype, cytokine production, proliferation and cytotoxic potential. Integrated data analysis was performed through correlation and principal component analysis of serum biomarkers and cellular immune responses. Forty-eight volunteers were included. The Ad26.ZEBOV, MVA-BN-Filo vaccine elicited: i) serum increase of inflammatory/activation markers mainly at 1 day after the Ad26.ZEBOV vaccine; ii) durable EBOV-specific T cell proliferation and CD8+ T cells exhibiting a cytotoxic phenotype after Ad26.ZEBOV prime, after MVA-BN-Filo boost and 6 months post vaccination. Integrated analysis revealed correlations between: i) EBOV-specific CD8+ T cell proliferation and cytotoxic phenotype; ii) high EBOV-specific CD8+ T cell cytotoxic phenotype and low inflammatory marker IL-8 at day 1 post vaccination. This study provides unique insights into the in vivo contribution of proliferation/cytotoxic CD8+ T cells and inflammation to the Ad26.ZEBOV, MVA-BN-Filo vaccine-induced potency.

Computational mining of B cell receptor repertoires reveals antigen-specific and convergent responses to Ebola vaccination.

Outbreaks of Ebolaviruses, such as Sudanvirus (SUDV) in Uganda in 2022, demonstrate that species other than the Zaire ebolavirus (EBOV), which is currently the sole virus represented in current licensed vaccines, remain a major threat to global health. There is a pressing need to develop effective pan-species vaccines and novel monoclonal antibody-based therapeutics for Ebolavirus disease. In response to recent outbreaks, the two dose, heterologous Ad26.ZEBOV/MVA-BN-Filo vaccine regimen was developed and was tested in a large phase II clinical trial (EBL2001) as part of the EBOVAC2 consortium. Here, we perform bulk sequencing of the variable heavy chain (VH) of B cell receptors (BCR) in forty participants from the EBL2001 trial in order to characterize the BCR repertoire in response to vaccination with Ad26.ZEBOV/MVA-BN-Filo. We develop a comprehensive database, EBOV-AbDab, of publicly available Ebolavirus-specific antibody sequences. We then use our database to predict the antigen-specific component of the vaccinee repertoires. Our results show striking convergence in VH germline gene usage across participants following the MVA-BN-Filo dose, and provide further evidence of the role of IGHV3-15 and IGHV3-13 antibodies in the B cell response to Ebolavirus glycoprotein. Furthermore, we found that previously described Ebola-specific mAb sequences present in EBOV-AbDab were sufficient to describe at least one of the ten most expanded BCR clonotypes in more than two thirds of our cohort of vaccinees following the boost, providing proof of principle for the utility of computational mining of immune repertoires.

Healthcare Providers' and Frontline Workers' Experiences of an Ebola Vaccine Trial in the Boende Health District of the Democratic Republic of the Congo.

This study explored the experiences of healthcare providers (HCPs) and frontline workers who were involved in an Ebola vaccine trial in the Democratic Republic of the Congo. The researchers interviewed a total of 99 participants (HCPs and frontline workers) living and working in the Boende health district during the period of the study, from February to March 2022. These individuals included a mix of trial participants and non-trial participants (staff of the trial, local health authorities, and head nurses of health centers). In-depth individual interviews, as well as focus group discussions (FGDs), were used to understand interviewees' experiences and perceptions. The data were analyzed to identify the main themes. The findings unveiled a multitude of positive experiences among interviewees/FGD participants. The commitment of the trial investigators to improve the study site and to equip the volunteers with necessary skills and knowledge greatly contributed to a positive trial experience. However, some interviewees felt that the reimbursement for time and travel expenses during their trial visits was insufficient in comparison with their expectations. Additionally, there were expressions of worry about the frequency of blood draws during scheduled trial visits. Our findings emphasize the critical importance of addressing and continuously considering the perspectives and concerns of trial participants before designing and implementing vaccine trials. By actively incorporating their inputs, researchers can mitigate concerns and tailor communication strategies, potentially enhancing the overall success and impact of the vaccine trial.

An ancillary care policy in a vaccine trial conducted in a resource-constrained setting: evaluation and policy recommendations

IntroductionClear guidelines to implement ancillary care (AC) in clinical trials conducted in resource-constrained settings are lacking. Here, we evaluate an AC policy developed for a vaccine trial in the Democratic...

Safety and Immunogenicity of an Accelerated Ebola Vaccination Schedule in People with and without Human Immunodeficiency Virus: A Randomized Clinical Trial.

The safety and immunogenicity of the two-dose Ebola vaccine regimen MVA-BN-Filo, Ad26.ZEBOV, 14 days apart, was evaluated in people without HIV (PWOH) and living with HIV (PLWH). In this observer-blind, placebo-controlled, phase 2 trial, healthy adults were randomized (4:1) to receive MVA-BN-Filo (dose 1) and Ad26.ZEBOV (dose 2), or two doses of saline/placebo, administered intramuscularly 14 days apart. The primary endpoints were safety (adverse events (AEs)) and immunogenicity (Ebola virus (EBOV) glycoprotein-specific binding antibody responses). Among 75 participants (n = 50 PWOH; n = 25 PLWH), 37% were female, the mean age was 44 years, and 56% were Black/African American. AEs were generally mild/moderate, with no vaccine-related serious AEs. At 21 days post-dose 2, EBOV glycoprotein-specific binding antibody responder rates were 100% among PWOH and 95% among PLWH; geometric mean antibody concentrations were 6286 EU/mL (n = 36) and 2005 EU/mL (n = 19), respectively. A total of 45 neutralizing and other functional antibody responses were frequently observed. Ebola-specific CD4+ and CD8+ T-cell responses were polyfunctional and durable to at least 12 months post-dose 2. The regimen was well tolerated and generated robust, durable immune responses in PWOH and PLWH. Findings support continued evaluation of accelerated vaccine schedules for rapid deployment in populations at immediate risk. Trial registration: NCT02598388 (submitted 14 November 2015).

Assessment of health care workers preparedness to epidemics: A case of Ebola virus disease preparedness in private hospitals in Kampala, Uganda.

Unrecognized Ebola Virus Disease (EVD) can lead to multiple chains of transmissions if the first caretakers are not trained and prepared. This study aimed to assess healthcare workers (HCWs) preparedness in private hospitals located in Kampala, to detect, respond and prevent EVD. A descriptive cross-sectional study was carried out among HCWs in direct clinical care provision in four private hospitals, and in one Ebola Treatment Unit (ETU) using a self-administered questionnaire from March to June 2020. 222 HCWs agreed to participate aged from 19 to 64 years and with 6 months to 38 years of practice where most were nurses (44%). 3/5 hospitals did not have written protocols on EVD case management, and only one (ETU) had an exclusive emergency team. 59% were not sure whether contact tracing was taking place. Private hospitals were not included in EVD trainings organized by the Ministry of Health (MoH). In addition, HCWs in private hospitals were not empowered by the MoH to take part in EVD case management. Despite these shortcomings, only 66% of HCWs showed an interest to be immunized. Knowledge about potential Ebola vaccines was generally poor. In Kampala, Uganda, establishment of a more comprehensive preparedness and response strategy for EVD outbreaks is imperative for HCWs in private facilities, including a wide vaccination educational program on Ebola vaccination. The findings from this study if addressed will likely improve the preparedness and management of future Ebola outbreaks in Uganda.

Use of Ebola Vaccines - Worldwide, 2021-2023.

Ebola virus disease (Ebola) is a rare but severe illness in humans, with an average case fatality rate of approximately 50%. Two licensed vaccines are currently available against Orthoebolavirus zairense, the virus that causes Ebola: the 1-dose rVSVΔG-ZEBOV-GP (ERVEBO [Merck]) and the 2-dose regimen of Ad26.ZEBOV and MVA-BN-Filo (Zabdeno/Mvabea [Johnson & Johnson]). The Strategic Advisory Group of Experts on Immunization recommends the use of 1-dose ERVEBO during Ebola outbreaks, and in 2021, a global stockpile of ERVEBO was established to ensure equitable, timely, and targeted access to vaccine doses for future Ebola outbreaks. This report describes the use of Ebola vaccines and the role of the stockpile developed and managed by the International Coordinating Group (ICG) on Vaccine Provision during 2021-2023. A total of 145,690 doses have been shipped from the ICG stockpile since 2021. However, because outbreaks since 2021 have been limited and rapidly contained, most doses (139,120; 95%) shipped from the ICG stockpile have been repurposed for preventive vaccination of high-risk groups, compared with 6,570 (5%) used for outbreak response. Repurposing doses for preventive vaccination could be prioritized in the absence of Ebola outbreaks to prevent transmission and maximize the cost-efficiency and benefits of the stockpile.

Is it fear or politics? A qualitative exploration of stakeholders’ views on the failed Ebola vaccine trial in Southern Ghana

Background: The negative meaning and rumours associated with the conduct of clinical trials regarding their experimental nature adversely affect trust and their conduct. A typical example of the challenges in conducting clinical trial studies was where Ghana was selected to conduct the ebola vaccine trials, which was not successful. This study explored the social and political perspectives on the unsuccessful implementation of the ebola vaccine trial in Ghana. Methods: This was a cross-sectional exploratory study using qualitative research approach where 31 in-depth individual interviews and Key informant interviews were conducted with participants. The interviews were recorded, transcribed and coded into themes using Nvivo 12 software to aid thematic content analysis. Results: The views expressed by participants suggested that lack of stakeholder engagement to create awareness on the Ebola vaccine trial led to doubts on the purpose for the trial. Also, media propaganda, negative influence and the perception that conducting the vaccine trial in Ghana could introduce the Ebola virus into the country created panic and fear, which affected public trust and support for the Ebola vaccine trial conduct in Ghana. Furthermore, political influence linked with site selection and timing for the study in particular, led to mistrust and the subsequent suspension of the trial in Ghana. Conclusions: Based on the interpretation of our data, we conclude that the indefinite suspension of the Ebola vaccine trial in Ghana could largely be attributed to both fear and political influence as well as misinformation resulting from media propaganda leading to mistrust.

Safety and Immunogenicity of Accelerated Heterologous 2-Dose Ebola Vaccine Regimens in Adults With and Without HIV in Africa.

Shorter prophylactic vaccine schedules may offer more rapid protection against Ebola in resource-limited settings. This randomized, observer-blind, placebo-controlled, phase 2 trial conducted in 5 sub-Saharan African countries included people without human immunodeficiency virus (HIV) (PWOH, n = 249) and people with HIV (PWH, n = 250). Adult participants received 1 of 2 accelerated Ebola vaccine regimens (MVA-BN-Filo, Ad26.ZEBOV administered 14 days apart [n = 79] or Ad26.ZEBOV, MVA-BN-Filo administered 28 days apart [n = 322]) or saline/placebo (n = 98). The primary endpoints were safety (adverse events [AEs]) and immunogenicity (Ebola virus [EBOV] glycoprotein-specific binding antibody responses). Binding antibody responders were defined as participants with a >2.5-fold increase from baseline or the lower limit of quantification if negative at baseline. The mean age was 33.4 years, 52% of participants were female, and among PWH, the median CD4+ cell count was 560.0 (interquartile range, 418.0-752.0) cells/μL. AEs were generally mild/moderate with no vaccine-related serious AEs or remarkable safety profile differences by HIV status. At 21 days post-dose 2, EBOV glycoprotein-specific binding antibody response rates in vaccine recipients were 99% for the 14-day regimen (geometric mean concentrations [GMCs]: 5168 enzyme-linked immunosorbent assay units [EU]/mL in PWOH; 2509 EU/mL in PWH) and 98% for the 28-day regimen (GMCs: 6037 EU/mL in PWOH; 2939 EU/mL in PWH). At 12 months post-dose 2, GMCs in PWOH and PWH were 635 and 514 EU/mL, respectively, for the 14-day regimen and 331 and 360 EU/mL, respectively, for the 28-day regimen. Accelerated 14- and 28-day Ebola vaccine regimens were safe and immunogenic in PWOH and PWH in Africa. Clinical Trials Registration. NCT02598388.

Engaging the public in decisions about emergency vaccine deployment strategies: Lessons from scenario-based discussions in Sierra Leone

ABSTRACT The COVID-19 pandemic has amplified discussions on emergency vaccine deployment strategies, with current perspectives often neglecting extensive community involvement in ethical, logistical and political aspects. Existing social science literature predominantly delves into factors influencing trust, overlooking the untapped potential for community engagement. Our study examines community preparedness in Sierra Leone’s Kambia District, exploring diverse viewpoints on vaccine deployment strategies, emphasising Ebola and COVID-19 vaccinations. Utilising extensive ethnographic research from the Ebola vaccine trials (EBOVAC Salone) conducted in Kambia District from 2015 to 2021, including participant observation and tailored focus group discussions, we investigated various deployment scenarios with community leaders and citizens. Our findings underscore the multifaceted contributions of social science research with communities in shaping emergency vaccination strategies. These contributions span logistical insights, aligning campaigns with local livelihoods and social structures, and grounded ethical concerns assessing social justice outcomes across epidemic scenarios. This study emphasises the imperative of integrating discussions on vaccine confidence and deployment. It highlights communities’ proficiency in epidemiological reasoning and their ability to bring this in conversation with salient socio-cultural, economic and religious dimensions. We therefore promote the cultivation of public dialogue, collaborative creation of impactful vaccination initiatives alongside relevant communities in recognition of their invaluable perspectives .

Helminth exposure and immune response to the two-dose heterologous Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen.

The exposure to parasites may influence the immune response to vaccines in endemic African countries. In this study, we aimed to assess the association between helminth exposure to the most prevalent parasitic infections, schistosomiasis, soil transmitted helminths infection and filariasis, and the Ebola virus glycoprotein (EBOV GP) antibody concentration in response to vaccination with the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen in African and European participants using samples obtained from three international clinical trials. We conducted a study in a subset of participants in the EBL2001, EBL2002 and EBL3001 clinical trials that evaluated the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen against EVD in children, adolescents and adults from the United Kingdom, France, Burkina Faso, Cote d'Ivoire, Kenya, Uganda and Sierra Leone. Immune markers of helminth exposure at baseline were evaluated by ELISA with three commercial kits which detect IgG antibodies against schistosome, filarial and Strongyloides antigens. Luminex technology was used to measure inflammatory and activation markers, and Th1/Th2/Th17 cytokines at baseline. The association between binding IgG antibodies specific to EBOV GP (measured on day 21 post-dose 2 and on Day 365 after the first dose respectively), and helminth exposure at baseline was evaluated using a multivariable linear regression model adjusted for age and study group. Seventy-eight (21.3%) of the 367 participants included in the study had at least one helminth positive ELISA test at baseline, with differences of prevalence between studies and an increased prevalence with age. The most frequently detected antibodies were those to Schistosoma mansoni (10.9%), followed by Acanthocheilonema viteae (9%) and then Strongyloides ratti (7.9%). Among the 41 immunological analytes tested, five were significantly (p < .003) lower in participants with at least one positive helminth ELISA test result: CCL2/MCP1, FGFbasic, IL-7, IL-13 and CCL11/Eotaxin compared to participants with negative helminth ELISA tests. No significant association was found with EBOV-GP specific antibody concentration at 21 days post-dose 2, or at 365 days post-dose 1, adjusted for age group, study, and the presence of any helminth antibodies at baseline. No clear association was found between immune markers of helminth exposure as measured by ELISA and post-vaccination response to the Ebola Ad26.ZEBOV/ MVA-BN-Filo vaccine regimen. NCT02416453, NCT02564523, NCT02509494. ClinicalTrials.gov.

Broken Promises: Prolonged Diminished Quality-of-Life among Liberian Ebola Survivors Half a Decade after the 2014-16 West African Outbreak

The 2014–2016 Ebola outbreak left thousands of Liberian survivors with severely diminished quality of life. Applying a social determinants framework, this mixed method study investigates to what extent Ebola virus disease (EVD) survivors suffer long-haul psychosocial stress, diminished quality-of-life factors, and the impact of EVD-related service provisions on their ongoing healing. We present the results of a quantitative analysis survey of data collected from 19 Liberian EVD survivors in 2022 using snowball sampling. Additionally, a qualitative analysis of survivor statements helps triangulate key statistical findings and inform causal mechanisms. Survivors report experiencing 5.25 of a total of 7 ongoing stressors (95% CI 4.65–5.85). Higher satisfaction rates of government service provision are negatively correlated with experiencing long-term stigmatization (&lt;em&gt;r&lt;/em&gt; = -0.55), eviction (-0.45), and the inability to pay school fees (-0.33). However, most survivors rate service provisions as low, frustrated that promised services such as resettlement and scholarships often have gone unfulfilled. All survivors feel the world has forgotten about them. All suffer financial hardships. The inability to fund their children’s schooling is statistically linked to experiencing 43 percent higher (2.96 points) stress than that of peers (&lt;em&gt;p&lt;/em&gt; &lt; 0.05). Due to ongoing EVD-related health complications, all survivors volunteered as human participants in the clinical trials mounted by Partnership for Research on Ebola Vaccines in Liberia (PREVAIL). Statements reflect diminishing implementation quality over time, along with instances of unethical mistreatment. Being treated poorly or being discriminated against by PREVAIL staff appears to have an 18 percent (1.27 points) higher rate of stress (&lt;em&gt;p&lt;/em&gt; &lt; 0.05). This research is one of the first studies that examines the long-term social adversities threatening survivors’ long-term well-being.

Perceptions, attitudes, and willingness of healthcare and frontline workers to participate in an Ebola vaccine trial in Uganda

BackgroundUnderstanding the knowledge, perception and attitudes towards Ebola vaccines is an important factor in ensuring future use of these vaccines. A qualitative methods study embedded in an Ebola vaccine immunogenicity and safety trial (NCT04028349) was conducted to explore the knowledge and perceptions of healthcare (HCWs) and frontline workers (FLWs), about Ebola vaccines and their willingness to participate or recommend participation in Uganda. MethodWe carried out focus group discussions and semi-structured interviews before and after vaccination, with 70 HCWs and FLWs who consented to participate in the trial, and in the qualitative component, from August to September 2019. Data were analysed using thematic content analysis. ResultsRespondents showed good knowledge about Ebola and the vaccines in general, and had wide access to information through several channels, including the study team. On prevention, particular attention was given to effective communication within health facilities. Misconceptions were mainly around route of transmission, animal origin and types of vaccines. Previous fears were based on rumours circulating in the community, mainly about the presence of the virus in the vaccine, side effects and intention to harm (e.g. by “the whites”), ultimately insisting on transparency, trust and involvement of local leaders. Acceptability of participation was motivated by the need to protect self and others, and the willingness to advance research. Majority were willing to recommend participation to their community. ConclusionsOverall, information sharing leads to a better understanding and acceptance of vaccine trials and a positive vaccination experience can be a deciding factor in the acceptance of others. Particular attention should be paid to involving the community in addressing misconceptions and fears, while ensuring that participants have access to vaccination sites in terms of transport, and that they are properly accommodated at the study site including staying for a reasonable period of time.

Effects of Shock and Vibration on Product Quality during Last-Mile Transportation of Ebola Vaccine under Refrigerated Conditions1.

Analyzing vaccine stability under different storage and transportation conditions is critical to ensure that effectiveness and safety are not affected by distribution. In a simulation of the last mile in the supply chain, we found that shock and vibration had no effect on Ad26.ZEBOV/MVA-BN-Filo Ebola vaccine regimen quality under refrigerated conditions.

Heterologous cAd3-Ebola and MVA-EbolaZ vaccines are safe and immunogenic in US and Uganda phase 1/1b trials

Ebola virus disease (EVD) is a filoviral infection caused by virus species of the Ebolavirus genus including Zaire ebolavirus (EBOV) and Sudan ebolavirus (SUDV). We investigated the safety and immunogenicity of a heterologous prime-boost regimen involving a chimpanzee adenovirus 3 vectored Ebola vaccine [either monovalent (cAd3-EBOZ) or bivalent (cAd3-EBO)] prime followed by a recombinant modified vaccinia virus Ankara EBOV vaccine (MVA-EbolaZ) boost in two phase 1/1b randomized open-label clinical trials in healthy adults in the United States (US) and Uganda (UG). Trial US (NCT02408913) enrolled 140 participants, including 26 EVD vaccine-naïve and 114 cAd3-Ebola-experienced participants (April-November 2015). Trial UG (NCT02354404) enrolled 90 participants, including 60 EVD vaccine-naïve and 30 DNA Ebola vaccine-experienced participants (February-April 2015). All tested vaccines and regimens were safe and well tolerated with no serious adverse events reported related to study products. Solicited local and systemic reactogenicity was mostly mild to moderate in severity. The heterologous prime-boost regimen was immunogenic, including induction of durable antibody responses which peaked as early as two weeks and persisted up to one year after each vaccination. Different prime-boost intervals impacted the magnitude of humoral and cellular immune responses. The results from these studies demonstrate promising implications for use of these vaccines in both prophylactic and outbreak settings.