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205 result(s)
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205 result(s)
Journal Article > ResearchFull Text

Using an analogue-digital hybrid clinical data management platform during a two-dose preventive Ebola virus vaccine trial in Goma, the Democratic Republic of the Congo

PLOS Glob Public Health. 2 May 2025; Volume 5 (Issue 5); e0004487.; DOI:10.1371/journal.pgph.0004487
Brindle HE, Tetsa-Tata D, Edwards T, Choi EML, Kasonia K,  et al.
PLOS Glob Public Health. 2 May 2025; Volume 5 (Issue 5); e0004487.; DOI:10.1371/journal.pgph.0004487

Clinical trials in settings with intermittent or non-existent internet and power connectivity, for example during humanitarian emergencies, present challenges in the synchronisation of data across different sites, in addition to accessing a centralised database in real-time. To overcome these, we designed a novel hybrid analogue/digital data management system which was deployed during the rapid implementation of a Phase III evaluation of a two-dose preventative vaccine for Ebola virus disease in Goma, Democratic Republic of the Congo, from 2019 to 2022. We provided study participants with an Enhanced Participant Record Card (EPRC) that served as eligibility for, and confirmation of, vaccination and was used in combination with Open Data Kit (ODK) electronic case report forms to create an off-grid study participant management system. To understand the utility of the EPRC, we analysed data from 15,327 study participants who received both vaccines and various types of prompts or reminders to return for dose 2, including home visits, telephone calls, or short messaging service (SMS). A total of 53% participants referred to the date on the EPRC as a prompt to return for dose 2 and 36.1% mentioned this as the only prompt. A multivariable generalised linear mixed-effects model showed that those who were not working, those aged 45–64 years or who had a chronic medical condition identified prior to receiving dose 2 were more likely to use the date on the EPRC as a prompt. Our findings demonstrate the utility of this system in the facilitation of decentralised data collection in off-grid locations that may be useful for future trials in complex humanitarian settings.

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Journal Article > ResearchFull Text

Evaluation of a decentralised model of care on case isolation and patient outcomes during the 2018–20 Ebola outbreak in the Democratic Republic of the Congo: a retrospective observational study

Lancet Global Health. 25 March 2025; Online ahead of print; DOI:10.1016/S2214-109X(25)00011-7
Barks PM, Camacho A, Newport T, Ribeiro F, Ahuka-Mundeke S,  et al.
Lancet Global Health. 25 March 2025; Online ahead of print; DOI:10.1016/S2214-109X(25)00011-7
Journal Article > ReviewFull Text

Ebola disease: Bridging scientific discoveries and clinical application

Lancet Infect Dis. 1 December 2024; Online ahead of print; DOI:10.1016/S1473-3099(24)00673-X
Rojek A, Fieggen J, Apiyo P, Caluwaerts S, Fowler RA,  et al.
Lancet Infect Dis. 1 December 2024; Online ahead of print; DOI:10.1016/S1473-3099(24)00673-X

The west Africa Ebola disease epidemic (2014-16) marked a historic change of course for patient care during emerging infectious disease outbreaks. The epidemic response was a failure in many ways-a slow, cumbersome, and disjointed effort by a global architecture that was not fit for purpose for a rapidly spreading outbreak. In the most affected countries, health-care workers and other responders felt helpless-dealing with an overwhelming number of patients but with few, if any, tools at their disposal to provide high-quality care. These inadequacies, however, led to attention and innovation. The decade since then has seen remarkable achievements in clinical care for Ebola disease, including the approval of the first vaccines and treatments. In this paper, the first in a two-part Series, we reflect on this progress and provide expert summary of the modern landscape of Ebola disease, highlighting the priorities and ongoing activities aimed at further improving patient survival and wellbeing in the years ahead.

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Journal Article > ResearchFull Text

rVSV-ZEBOV vaccination in people with pre-existing immunity to Ebolavirus: an open-label safety and immunogenicity study in Guinean communities affected by Ebola virus disease (l’essai proches)

BMC Med. 7 November 2024; Volume 22 (Issue 1); 523.; DOI:10.1186/s12916-024-03726-z
Watson CH, Gsell PS, Hall Y, Camacho A, Riveros X,  et al.
BMC Med. 7 November 2024; Volume 22 (Issue 1); 523.; DOI:10.1186/s12916-024-03726-z

BACKGROUND

Zaire Ebolavirus disease (EVD) outbreaks can be controlled using rVSV-ZEBOV vaccination and other public health measures. People in high-risk areas may have pre-existing antibodies from asymptomatic Ebolavirus exposure that might affect response to rVSV-ZEBOV. Therefore, we assessed the impact pre-existing immunity had on post-vaccination IgG titre, virus neutralisation, and reactogenicity following vaccination.


METHODS

In this prospective cohort study, 2115 consenting close contacts (“proches”) of EVD survivors were recruited. Proches were vaccinated with rVSV-ZEBOV and followed up for 28 days for safety and immunogenicity. Anti-GP IgG titre at baseline and day 28 was assessed by ELISA. Samples from a representative subset were evaluated using live virus neutralisation.


RESULTS

Ten percent were seropositive at baseline. At day 28, IgG in baseline seronegative (GMT 0.106 IU/ml, 95% CI: 0.100 to 0.113) and seropositive (GMT 0.237 IU/ml, 0.210 to 0.267) participants significantly increased from baseline (both p < 0.0001). There was strong correlation between antibody titres and virus neutralisation in day 28 samples (Spearman’s rho 0.75). Vaccinees with baseline IgG antibodies against Zaire Ebolavirus had similar safety profiles to those without detectable antibodies (63.6% vs 66.1% adults experienced any adverse event; 49.1% vs 60.9% in children), with almost all adverse events graded as mild. No serious adverse events were attributed to vaccination. No EVD survivors tested positive for Ebolavirus by RT-PCR.


CONCLUSIONS

These data add further evidence of rVSV-ZEBOV safety and immunogenicity, including in people with pre-existing antibodies from suspected natural ZEBOV infection whose state does not blunt rVSV-ZEBOV immune response. Pre-vaccination serological screening is not required.

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Journal Article > ReviewFull Text

Improving Ebola virus disease outbreak control through targeted post-exposure prophylaxis

Lancet Healthy Longev Healthy longevity. 10 September 2024; Volume 12 (Issue 10); e1730 - e1736.; DOI:10.1016/S2214-109X(24)00255-9
Elin Hoffmann Dahl, Prof Placide Mbala, Sylvain Juchet, Prof Abdoulaye Touré, Alice Montoyo,  et al.
Lancet Healthy Longev Healthy longevity. 10 September 2024; Volume 12 (Issue 10); e1730 - e1736.; DOI:10.1016/S2214-109X(24)00255-9
Journal Article > Short ReportFull Text

Evaluation of centralised and decentralised models of care during the 2020 Ebola Virus Disease outbreak in Equateur Province, Democratic Republic of the Congo: A brief report

F1000Research. 28 August 2024; Volume 13 (Issue 642); DOI:10.12688/f1000research.150755.2
Lampaert E, Nsio JM, Nair D, Mashako M, De Weggheleire A,  et al.
F1000Research. 28 August 2024; Volume 13 (Issue 642); DOI:10.12688/f1000research.150755.2

BACKGROUND

Traditionally in the Democratic Republic of the Congo (DRC), centralised Ebola treatment centres (ETCs) have been set exclusively for Ebola virus disease (EVD) case management during outbreaks. During the 2020 EVD outbreak in DRC’s Equateur Province, existing health centres were equipped as decentralised treatment centres (DTC) to improve access for patients with suspected EVD. Between ETCs and DTCs, we compared the time from symptom onset to admission and diagnosis among patients with suspected EVD.

METHODS

This was a cohort study based on analysis of a line-list containing demographic and clinical information of patients with suspected EVD admitted to any EVD health facility during the outbreak.

RESULTS

Of 2359 patients with suspected EVD, 363 (15%) were first admitted to a DTC. Of 1996 EVD-suspected patients initially admitted to an ETC, 72 (4%) were confirmed as EVD-positive. Of 363 EVD-suspected patients initially admitted to a DTC, 6 (2%) were confirmed and managed as EVD-positive in the DTC. Among all EVD-suspected patients, the median (interquartile range) duration between symptom onset and admission was 2 (1-4) days in a DTC compared to 4 (2-7) days in an ETC (p<0.001). Similarly, time from symptom onset to admission was significantly shorter among EVD-suspected patients ultimately diagnosed as EVD-negative.

CONCLUSIONS

Since <5% of the EVD-suspected patients admitted were eventually diagnosed with EVD, there is a need for better screening to optimise resource utilization and outbreak control. Only one in seven EVD-suspected patients were admitted to a DTC first, as the DTCs were piloted in a limited and phased manner. However, there is a case to be made for considering decentralized care especially in remote and hard-to-reach areas in places like the DRC to facilitate early access to care, contain viral shedding by patients with EVD and ensure no disrupted provision of non-EVD services.

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Journal Article > Case Report/SeriesFull Text

Effectiveness of rVSV-ZEBOV vaccination during the 2018–20 Ebola virus disease epidemic in the Democratic Republic of the Congo: a retrospective test-negative study

Lancet Infect Dis. 1 August 2024; Online ahead of print; DOI:10.1016/S1473-3099(24)00419-5
Meakin S, Nsio J, Camacho A, Kitenge R, Coulborn RM,  et al.
Lancet Infect Dis. 1 August 2024; Online ahead of print; DOI:10.1016/S1473-3099(24)00419-5

BACKRGOUND

The recombinant vesicular stomatitis virus-Zaire Ebola virus (rVSV-ZEBOV) vaccine is the only WHO prequalified vaccine recommended for use to respond to outbreaks of Ebola virus (species Zaire ebolavirus) by WHO's Strategic Advisory Group of Experts on Immunization. Despite the vaccine's widespread use during several outbreaks, no real-world effectiveness estimates are currently available in the literature.


METHODS

We conducted a retrospective test-negative analysis to estimate effectiveness of rVSV-ZEBOV vaccination against Ebola virus disease during the 2018-20 epidemic in the Democratic Republic of the Congo, using data on suspected Ebola virus disease cases collected from Ebola treatment centres. Those eligible for inclusion had an available Ebola virus RT-PCR result, available key data, were eligible for vaccination during the outbreak, and had symptom onset aligning with the period in which a ring-vaccination protocol was in use. After imputing missing data, each individual confirmed by RT-PCR to be Ebola virus disease-positive (defined as a case) was matched to one individual negative for Ebola virus disease (control) by sex, age, health zone, and month of symptom onset. Effectiveness was estimated from the odds ratio of being vaccinated (≥10 days before symptom onset) versus being unvaccinated among cases and controls, after adjusting for the matching factors. The imputation, matching and effectiveness estimation, was repeated 500 times.


FINDINGS

1273 (4·8%) of 26 438 eligible individuals were positive for Ebola virus disease (cases) and 25 165 (95·2%) were negative (controls). 40 (3·1%) cases and 1271 (5·1%) controls were reported as being vaccinated at least 10 days before symptom onset. After selecting individuals who reported exposure to an individual with Ebola virus disease within the 21 days before symptom onset and matching, the analysis datasets comprised a median of 309 cases and 309 controls. 10 days or more after vaccination, the effectiveness of rVSV-ZEBOV against Ebola virus disease was estimated to be 84% (95% credible interval 70-92).


INTERPRETATION

This analysis is the first to provide estimates of the real-world effectiveness of the rVSV-ZEBOV vaccine against Ebola virus disease, amid the widespread use of the vaccine during a large Ebola virus disease outbreak. Our findings confirm that rVSV-ZEBOV is highly protective against Ebola virus disease and support its use during outbreaks, even in challenging contexts such as in the eastern Democratic Republic of the Congo.

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Journal Article > ResearchFull Text

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

Vaccines. 26 July 2024; Volume 12 (Issue 8); 828.; DOI:10.3390/vaccines12080828
Choi EM, Kasonia K, Kavunga-Membo H, Mukadi-Bamuleka D, Soumah A,  et al.
Vaccines. 26 July 2024; Volume 12 (Issue 8); 828.; DOI:10.3390/vaccines12080828

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.

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Journal Article > ResearchFull Text

Delivery and safety of a two-dose preventive Ebola virus disease vaccine in pregnant and non-pregnant participants during an outbreak in the Democratic Republic of the Congo

Vaccines. 23 July 2024; Volume 12 (Issue 8); 825.; DOI:10.3390/vaccines12080825
Kavunga-Membo H, Watson-Jones D, Kasonia K, Edwards T, Camacho A,  et al.
Vaccines. 23 July 2024; Volume 12 (Issue 8); 825.; DOI:10.3390/vaccines12080825

During the 2018–2020 Ebola virus disease (EVD) outbreak, residents in Goma, Democratic Republic of the Congo, were offered a two-dose prophylactic EVD vaccine. This was the first study to evaluate the safety of this vaccine in pregnant women. Adults, including pregnant women, and children aged ≥1 year old were offered the Ad26.ZEBOV (day 0; dose 1), MVA-BN-Filo (day 56; dose 2) EVD vaccine through an open-label clinical trial. In total, 20,408 participants, including 6635 (32.5%) children, received dose 1. Fewer than 1% of non-pregnant participants experienced a serious adverse event (SAE) following dose 1; one SAE was possibly related to the Ad26.ZEBOV vaccine. Of the 1221 pregnant women, 371 (30.4%) experienced an SAE, with caesarean section being the most common event. No SAEs in pregnant women were considered related to vaccination. Of 1169 pregnancies with a known outcome, 55 (4.7%) ended in a miscarriage, and 30 (2.6%) in a stillbirth. Eleven (1.0%) live births ended in early neonatal death, and five (0.4%) had a congenital abnormality. Overall, 188/891 (21.1%) were preterm births and 79/1032 (7.6%) had low birth weight. The uptake of the two-dose regimen was high: 15,328/20,408 (75.1%). The vaccine regimen was well-tolerated among the study participants, including pregnant women, although further data, ideally from controlled trials, are needed in this crucial group.

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Conference Material > Abstract

Effectiveness of rVSV-ZEBOV vaccination during the 10th Ebola virus disease epidemic in the Democratic Republic of the Congo: a retrospective observational analysis

Meakin S
Epicentre Scientific Day 2024. 23 May 2024
BACKGROUND
The recombinant vesicular stomatitis virus–Zaire Ebola virus (rVSV-ZEBOV) vaccine is the only vaccine recommended for use to respond to Zaire ebolavirus outbreaks by SAGE. A single ring vaccination trial found the efficacy to be 100%; however, no estimates of real-world effectiveness have yet been published.

METHODS
We conducted a retrospective test-negative case-control analysis to estimate effectiveness of rVSV-ZEBOV vaccination against Ebola virus disease (EVD) during the 2018 - 2020 epidemic in the Democratic Republic of the Congo (DRC), using data on suspected cases collected at Ebola treatment centres. Missing data were imputed using multivariate imputation. Among those who reported contact with an Ebola case before symptom onset, each EVD-positive case was matched to one EVD-negative control by sex, age, health zone and month of symptom onset. Effectiveness was then estimated from the odds ratio of being vaccinated vs. unvaccinated among cases and controls, after adjusting for the matching factors.

RESULTS
The primary study population contained 309 cases and controls each, on average, of which between 11 and 23 cases (3.6– 7.4%) and between 48 and 80 controls (16 – 26%) were recorded as vaccinated at least ten days before symptom onset. We found rVSV-ZEBOV vaccination at least ten days before symptom onset was 84% effective against developing EVD (95% credible interval [70%, 92%]). There was no apparent difference in effectiveness by sex, age, or due to a change in vaccination protocol.

CONCLUSION
This study is the first to estimate real-world effectiveness of rVSV-ZEBOV vaccination EVD during the second largest EVD outbreak ever recorded. Our findings confirm that rVSV-ZEBOV vaccination is highly protective against developing EVD and support its reactive, targeted use in at-risk people during future outbreaks.
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