Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 1.890
Filter
1.
Vaccine ; 42(12): 3002-3008, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38565464

ABSTRACT

BACKGROUND: Understanding 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. METHOD: We 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. RESULTS: Respondents 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. CONCLUSIONS: Overall, 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.


Subject(s)
Ebola Vaccines , Hemorrhagic Fever, Ebola , Humans , Ebola Vaccines/adverse effects , Hemorrhagic Fever, Ebola/prevention & control , Uganda , Vaccination , Patient Acceptance of Health Care , Health Facilities
2.
Belitung Nurs J ; 10(1): 67-77, 2024.
Article in English | MEDLINE | ID: mdl-38425680

ABSTRACT

Background: The Ebola virus, a highly infectious and deadly pathogen, has posed a significant public health threat in West Africa for several decades. Liberia is one of the most severely affected countries. Healthcare personnel, including nurses, are on the front lines of patient care, and their perspectives are invaluable in understanding the challenges that arise during outbreaks, especially in implementing prevention measures. Objective: This study aimed to explore the potential risk components and prevention measures of the Ebola virus disease (EVD). Methods: This study used an exploratory descriptive qualitative design. Five stakeholders, ten doctors and five nurses who had suffered from EVD during the outbreak in Liberia participated in semi-structured interviews to provide their experience and comprehensive perspectives on EVD. Data were collected from February 2022-August 2023. NVivo 12 plus was used for inductive thematic analysis. Results: Six themes and several subthemes emerged: 1) transmission modes (body contact, body fluid, sexual intercourse, traditional burial), 2) funeral attendance (traditional practices and crowded gatherings), 3) community-led prevention (promoting good hygiene practices, increasing awareness, contact tracing, and surveillance), 4) Ebola virus vaccine (false sense of security, potential side effects, and limited data), 5) challenges in implementing prevention measures (inadequate health infrastructures, difficulty of tracing infected people, lack of resources, and cultural-social barriers), 6) Liberia's health systems (a weak, underfunded, fragile health infrastructure, lack of health facilities and shortage of health workers). Conclusion: Several potential risk components contributing to the EVD outbreak should be a public concern. Strengthening the current healthcare system supported by local community and international aid providers (multidisciplinary teams) is needed to anticipate behavioral problems and to improve the efficacy of the prevention measures appropriate to the conditions in Liberia. Accordingly, the nurses' compliance with the recommended prevention practices is necessary.

3.
Lancet Infect Dis ; 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38340736

ABSTRACT

BACKGROUND: The rVSVΔG-ZEBOV-GP vaccine constitutes a valuable tool to control Ebola virus disease outbreaks. This retrospective cohort study aimed to assess the protective effect of the vaccine against death among patients with confirmed Ebola virus disease. METHODS: In this retrospective cohort analysis of patients with confirmed Ebola virus disease admitted to Ebola health facilities in the Democratic Republic of the Congo between July 27, 2018, and April 27, 2020, we performed univariate and multivariate analyses to assess case fatality risk and cycle threshold for nucleoprotein according to vaccination status, Ebola virus disease-specific treatments (eg, mAb114 and REGN-EB3), and other risk factors. FINDINGS: We analysed all 2279 patients with confirmed Ebola virus disease. Of these 2279 patients, 1300 (57%) were female and 979 (43%) were male. Vaccination significantly lowered case fatality risk (vaccinated: 25% [106/423] vs not vaccinated: 56% [570/1015]; p<0·0001). In adjusted analyses, vaccination significantly lowered the risk of death compared with no vaccination, with protection increasing as time elapsed from vaccination to symptom onset (vaccinated ≤2 days before onset: 27% [27/99], adjusted relative risk 0·56 [95% CI 0·36-0·82, p=0·0046]; 3-9 days before onset: 20% [28/139], 0·44 [0·29-0·65, p=0·0001]; ≥10 days before onset: 18% [12/68], 0·40 [0·21-0·69; p=0·0022]; vaccination date unknown: 33% [39/117], 0·69 [0·48-0·96; p=0·0341]; and vaccination status unknown: 52% [441/841], 0·80 [0·70-0·91, p=0·0011]). Longer time from symptom onset to admission significantly increased risk of death (49% [1117/2279], 1·03 [1·02-1·05; p<0·0001]). Cycle threshold values for nucleoprotein were significantly higher-indicating lower viraemia-among patients who were vaccinated compared with those who were not vaccinated; the highest difference was observed among those vaccinated 21 days or longer before symptom onset (median 30·0 cycles [IQR 24·6-33·7]) compared with patients who were not vaccinated (21·4 cycles [18·4-25·9], p<0·0001). INTERPRETATION: To our knowledge, this is the first observational study describing the protective effect of rVSVΔG-ZEBOV-GP vaccination against death among patients with confirmed Ebola virus disease admitted to an Ebola health facility. Vaccination was protective against death for all patients, even when adjusted for Ebola virus disease-specific treatment, age group, and time from symptom onset to admission. FUNDING: Médecins Sans Frontières. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

4.
Vaccines (Basel) ; 12(2)2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38400193

ABSTRACT

In this prospective, observational study (ClinicalTrials.gov Identifier: NCT02661464), long-term safety information was collected from participants previously exposed to the Ebola vaccines Ad26.ZEBOV and/or MVA-BN-Filo while enrolled in phase 1, 2, or 3 clinical studies. The study was conducted at 15 sites in seven countries (Burkina Faso, France, Kenya, Tanzania, Uganda, the United Kingdom, and the United States). Adult participants and offspring from vaccinated female participants who became pregnant (estimated conception ≤28 days after vaccination with MVA-BN-Filo or ≤3 months after vaccination with Ad26.ZEBOV) were enrolled. Adults were followed for 60 months after their first vaccination, and children born to female participants were followed for 60 months after birth. In the full analysis set (n = 614 adults; median age [range]: 32.0 [18-65] years), 49 (8.0%) had ≥1 serious adverse event (SAE); the incidence rate of any SAE was 27.4 per 1000 person-years (95% confidence interval: 21.0, 35.2). The unrelated SAEs of malaria were reported in the two infants in the full analysis set, aged 11 and 18 months; both episodes were resolved. No deaths or life-threatening SAEs occurred during the study. Overall, no major safety issues were identified; one related SAE was reported. These findings support the long-term clinical safety of the Ad26.ZEBOV and MVA-BN-Filo vaccines.

5.
Article in English | MEDLINE | ID: mdl-38372893

ABSTRACT

BACKGROUND: In 2021, an Ebola virus disease (EVD) outbreak was declared in Guinea, linked to persistent virus from the 2014-2016 West Africa Epidemic. This paper analyzes factors associated with contact tracing reliability (defined as completion of a 21-day daily follow-up) during the 2021 outbreak, and transitively, provides recommendations for enhancing contact tracing reliability in future. METHODS: We conducted a descriptive and analytical cross-sectional study using multivariate regression analysis of contact tracing data from 1071 EVD contacts of 23 EVD cases (16 confirmed and 7 probable). RESULTS: Findings revealed statistically significant factors affecting contact tracing reliability. Unmarried contacts were 12.76× more likely to miss follow-up than those married (OR = 12.76; 95% CI [3.39-48.05]; p < 0.001). Rural-dwelling contacts had 99% lower odds of being missed during the 21-day follow-up, compared to those living in urban areas (OR = 0.01; 95% CI [0.00-0.02]; p < 0.01). Contacts who did not receive food donations were 3× more likely to be missed (OR = 3.09; 95% CI [1.68-5.65]; p < 0.001) compared to those who received them. Contacts in health areas with a single team were 8× more likely to be missed (OR = 8.16; 95% CI [5.57-11.96]; p < 0.01) than those in health areas with two or more teams (OR = 1.00; 95% CI [1.68-5.65]; p < 0.001). Unvaccinated contacts were 30.1× more likely to be missed compared to vaccinated contacts (OR = 30.1; 95% CI [5.12-176.83]; p < 0.001). CONCLUSION: Findings suggest that contact tracing reliability can be significantly influenced by various demographic and organizational factors. Considering and understanding these factors-and where possible addressing them-may be crucial when designing and implementing contact tracing strategies during future outbreaks in low-resource settings.

7.
Lancet Microbe ; 5(2): e109-e118, 2024 02.
Article in English | MEDLINE | ID: mdl-38278165

ABSTRACT

BACKGROUND: The Democratic Republic of the Congo has had 15 Ebola virus disease (EVD) outbreaks, from 1976 to 2023. On June 1, 2020, the Democratic Republic of the Congo declared an outbreak of EVD in the western Équateur Province (11th outbreak), proximal to the 2018 Tumba and Bikoro outbreak and concurrent with an outbreak in the eastern Nord Kivu Province. In this Article, we assessed whether the 11th outbreak was genetically related to previous or concurrent EVD outbreaks and connected available epidemiological and genetic data to identify sources of possible zoonotic spillover, uncover additional unreported cases of nosocomial transmission, and provide a deeper investigation into the 11th outbreak. METHODS: We analysed epidemiological factors from the 11th EVD outbreak to identify patient characteristics, epidemiological links, and transmission modes to explore virus spread through space, time, and age groups in the Équateur Province, Democratic Republic of the Congo. Trained field investigators and health professionals recorded data on suspected, probable, and confirmed cases, including demographic characteristics, possible exposures, symptom onset and signs and symptoms, and potentially exposed contacts. We used blood samples from individuals who were live suspected cases and oral swabs from individuals who were deceased to diagnose EVD. We applied whole-genome sequencing of 87 available Ebola virus genomes (from 130 individuals with EVD between May 19 and Sept 16, 2020), phylogenetic divergence versus time, and Bayesian reconstruction of phylogenetic trees to calculate viral substitution rates and study viral evolution. We linked the available epidemiological and genetic datasets to conduct a genomic and epidemiological study of the 11th EVD outbreak. FINDINGS: Between May 19 and Sept 16, 2020, 130 EVD (119 confirmed and 11 probable) cases were reported across 13 Équateur Province health zones. The individual identified as the index case reported frequent consumption of bat meat, suggesting the outbreak started due to zoonotic spillover. Sequencing revealed two circulating Ebola virus variants associated with this outbreak-a Mbandaka variant associated with the majority (97%) of cases and a Tumba-like variant with similarity to the ninth EVD outbreak in 2018. The Tumba-like variant exhibited a reduced substitution rate, suggesting transmission from a previous survivor of EVD. INTERPRETATION: Integrating genetic and epidemiological data allowed for investigative fact-checking and verified patient-reported sources of possible zoonotic spillover. These results demonstrate that rapid genetic sequencing combined with epidemiological data can inform responders of the mechanisms of viral spread, uncover novel transmission modes, and provide a deeper understanding of the outbreak, which is ultimately needed for infection prevention and control during outbreaks. FUNDING: WHO and US Centers for Disease Control and Prevention.


Subject(s)
Ebolavirus , Hemorrhagic Fever, Ebola , United States , Humans , Animals , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , Retrospective Studies , Democratic Republic of the Congo/epidemiology , Phylogeny , Bayes Theorem , Ebolavirus/genetics , Disease Outbreaks , Genomics , Zoonoses/epidemiology
8.
PLOS Glob Public Health ; 4(1): e0002566, 2024.
Article in English | MEDLINE | ID: mdl-38236844

ABSTRACT

The tenth Ebola Virus Disease (EVD) outbreak (2018-2020, North Kivu, Ituri, South Kivu) in the Democratic Republic of the Congo (DRC) was the second-largest EVD outbreak in history. During this outbreak, Ebola vaccination was an integral part of the EVD response. We evaluated community perceptions toward Ebola vaccination and identified correlates of Ebola vaccine uptake among high-risk community members in North Kivu, DRC. In March 2021, a cross-sectional survey among adults was implemented in three health zones. We employed a sampling approach mimicking ring vaccination, targeting EVD survivors, their household members, and their neighbors. Outbreak experiences and perceptions toward the Ebola vaccine were assessed, and modified Poisson regression was used to identify correlates of Ebola vaccine uptake among those offered vaccination. Among the 631 individuals surveyed, most (90.2%) reported a high perceived risk of EVD and 71.6% believed that the vaccine could reduce EVD severity; however, 63.7% believed the vaccine had serious side effects. Among the 474 individuals who had been offered vaccination, 397 (83.8%) received the vaccine, 180 (45.3%) of those vaccinated received the vaccine after two or more offers. Correlates positively associated with vaccine uptake included having heard positive information about the vaccine (RR 1.30, 95% CI 1.06-1.60), the belief that the vaccine could prevent EVD (RR 1.23, 95% CI 1.09-1.39), and reporting that religion influenced all decisions (RR 1.13, 95% CI 1.02-1.25). Ebola vaccine uptake was high in this population, although mixed attitudes and vaccine delays were common. Communicating positive vaccine information, emphasizing the efficacy of the Ebola vaccine, and engaging religious leaders to promote vaccination may aid in increasing Ebola vaccine uptake during future outbreaks.

9.
Lancet Infect Dis ; 24(3): 266-274, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38043556

ABSTRACT

BACKGROUND: The use of specific anti-Ebola virus therapy, especially monoclonal antibodies, has improved survival in patients with Ebola virus disease. We aimed to assess the effect of monoclonal antibodies on anti-Ebola virus antibody responses in survivors of the 2018-20 Ebola outbreak in the Democratic Republic of the Congo. METHODS: In this observational prospective cohort study, participants were enrolled at three Ebola survivor clinics in Beni, Mangina, and Butembo (Democratic Republic of the Congo). Eligible children and adults notified as survivors of Ebola virus disease (ie, who had confirmed Ebola virus disease [RT-PCR positive in blood sample] and were subsequently declared recovered from the virus [RT-PCR negative in blood sample] with a certificate of recovery from Ebola virus disease issued by an Ebola treatment centre) during the 2018-20 Ebola virus disease outbreak were invited to participate in the study. Participants were recruited on discharge from Ebola treatment centres and followed up for 12-18 months depending on recruitment date. Routine follow-up assessments were done at 1, 3, 6, and 12-18 months after inclusion. We collected sociodemographic (age, sex, visit site), clinical (anti-Ebola virus drugs), and laboratory data (RT-PCR and Ct values). The primary outcome was the antibody concentrations against Ebola virus glycoprotein, nucleoprotein, and 40-kDa viral protein antigens over time assessed in all participants. Antibody concentrations were measured by the multiplex immunoassay, and the association between anti-Ebola virus antibody levels and the relevant exposures, such as anti-Ebola virus disease drugs (ansuvimab, REGN-EB3, ZMapp, or remdesivir), was assessed using both linear and logistic mixed regression models. This study is registered at ClinicalTrials.gov, NCT04409405. FINDINGS: Between April 16, 2020, and Oct 18, 2021, 1168 survivors were invited to participate in the Les Vainqueurs d'Ebola cohort study. 787 survivors were included in the study, of whom 358 had data available for antibody responses. 85 (24%) of 358 were seronegative for at least two Ebola virus antigens on discharge from the Ebola treatment centre. The antibody response over time fluctuated but a continuous decrease in an overall linear evolution was observed. Quantitative modelling showed a decrease in nucleoprotein, glycoprotein, and VP-40 antibody concentrations over time (p<0·0001) with the fastest decrease observed for glycoprotein. The probability of being seropositive for at least two antigens after 36 months was 53·6% (95% CI 51·6-55·6) for participants who received ansuvimab, 73·5% (71·5-75·5) for participants who received REGN-EB3, 76·8% (74·8-78·8) for participants who received remdesivir, and 78·5% (76·5-80·5) for participants who received ZMapp. INTERPRETATION: Almost a quarter of survivors were seronegative on discharge from the Ebola treatment centre and antibody concentrations decreased rapidly over time. These results indicate that monoclonal antibodies might negatively affect the production of anti-Ebola virus antibodies in survivors of Ebola virus disease which could increase the risk of reinfection or reactivation. FUNDING: The French National Agency for AIDS Research-Emergent Infectious Diseases-The French National Institute of Health and Medical Research, the French National Research Institute for Development, and the European and Developing Countries Clinical Trials Partnership. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Subject(s)
Ebolavirus , Hemorrhagic Fever, Ebola , Adult , Child , Humans , Hemorrhagic Fever, Ebola/drug therapy , Hemorrhagic Fever, Ebola/epidemiology , Antibody Formation , Cohort Studies , Prospective Studies , Democratic Republic of the Congo/epidemiology , Antibodies, Viral , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal/pharmacology , Survivors , Glycoproteins , Nucleoproteins/pharmacology , Nucleoproteins/therapeutic use
10.
J Infect Public Health ; 17(1): 35-43, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37992432

ABSTRACT

BACKGROUND: Evidence has demonstrated a high proportion of Ebola virus disease (EVD) survivors experienced stigma due to the disease. This study sought to understand the longer-term effects of stigma encountered by survivors of the 2014-2016 EVD epidemic living in Sierra Leone. METHODS: This was a cross-sectional study of 595 EVD survivors and 403 close contacts (n = 998) from Sierra Leone. Assessments were conducted using a three-part survey between November 2021 to March 2022. We explored the socio-demographic factors associated with stigma experienced by EVD survivors. FINDINGS: 50·6 % (n = 301) of EVD survivors reported that they continued to experience at least one aspect of stigma. Females were disproportionately affected by stigma, with 45·2 % of females reporting isolation from friends and family compared to 33·9 % of men (p = 0·005). Multivariable logistic regression models revealed those aged 40-44, living rurally, and reporting an acute infection longer than seven days was associated with EVD-related stigma at the time of survey. INTERPRETATION: This study demonstrates stigma is still prevalent among people who survived EVD in 2022. It also identified socio-demographic factors associated with stigma that can be used for targeting interventions. Importantly, this highlights the continued need for EVD survivors to access mental healthcare and social support systems well after disease recovery. FUNDING: This study was funded by the Canadian Institutes for Health Research (Grant no. PJT-175098. JK is funded by a Tier 2 Canada Research Chair in the Molecular Pathogenesis of Emerging and Re-Emerging Viruses. SS is funded by a Tier 2 Canada Research Chair in Program Science and Global Public Health.


Subject(s)
Hemorrhagic Fever, Ebola , Male , Female , Humans , Hemorrhagic Fever, Ebola/epidemiology , Stereotyping , Cross-Sectional Studies , Sierra Leone/epidemiology , Canada , Survivors , Disease Outbreaks
11.
J Community Health ; 49(1): 108-116, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37531047

ABSTRACT

The 2014-2016 West Africa Ebola outbreak was the largest in history, resulting in approximately 11,000 deaths. Despite the outbreak's eventual end, national and international health sensitization and containment efforts were subject to criticism. This study investigates disease-related knowledge and beliefs, as well as trusted sources of health information among EVD-survivors and their family members, highlighting the importance of community-informed public health responses. Participants (n = 134) were adults who were either EVD-infected, affected families/caregivers, or community leaders. In-depth interviews and focus groups explored EVD-related experiences, including health effects, stigma, and community relationships. Using a grounded theory and thematic content analysis approach, transcripts were coded for evidence of health sensitization, as well as compliance with mitigation measures and trusted sources of information. Participants displayed a high level of knowledge around EVD and reported compliance with mandated and personal prevention measures. Levels of health sensitization and subsequent reintegration of survivors were reported to be largely the products of community-based efforts, rather than the top-down, national public health response. Primary sources of trusted information included EVD survivors acting as peer educators; local leaders; and EVD sensitization by community health workers. This study highlights the importance of a community-based response for increasing the effectiveness of public health campaigns. Participants expressed that relying on the experiences of trusted cultural insiders led to a deeper understanding of Ebola compared to top-down public health campaigns, and helped infected and affected community members reintegrate. Future public health efforts should incorporate community-based participatory approaches to address infectious disease outbreaks.


Subject(s)
Hemorrhagic Fever, Ebola , Adult , Humans , Hemorrhagic Fever, Ebola/epidemiology , Sierra Leone/epidemiology , Disease Outbreaks/prevention & control , Family , Health Promotion
12.
Global Health ; 19(1): 96, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-38053050

ABSTRACT

BACKGROUND: Recent case studies indicate that the 2014-2016 Ebola outbreak, one of the worst pre-2020 global biological catastrophes in modern history, helped some nations to better prepared their responses for the COVID-19 pandemic. While such national case studies explore how specific nations applied EVD-related policies in their domestic battle against the COVID-19 pandemic, there is no known study that assesses how many WHO nations learned from the West African crisis and to what scale. OBJECTIVE: Applying the policy legacies analytical framework and a systematized literature review, this research examines how prior policy experiences with the 2014-16 EVD crisis as a large-scale emergent outbreak helped to inform and to condition WHO nations to proactively prepare their national policies and health systems for future threats, including ultimately COVID-19. METHODS: A systematized literature review of 803 evaluated sources assesses to what extent Ebola-affected and non-affected nations directly modified governmental health systems in relation to this warning. The study further evaluates how nations with documented Ebola-related changes fared during COVID-19 compared to nations that did not. We present a categorical theoretical framework that allows for classifying different types of national response activities (termed conditioned learning). RESULTS: Ten (90.9%) of 11 nations that were affected by 2014-16 Ebola crisis have documented evidence of repurposing their EVD-related policies to fight COVID-19. 164 (70.0%) of 234 non-EVD-affected nations had documented evidence of specifically adapting national systems to incorporate policy recommendations developed from the 2014-16 crisis, which informed their COVID-19 responses in 2020. CONCLUSIONS: The shock of 2014-16 EVD outbreak affected most nations around the world, whether they experienced Ebola cases. We further develop a categorical framework that helps characterised nations previous experiences with this biological catastrophe, providing a means to analyse to what extent that individual nations learned and how these EVD-related changes helped inform their COVID-19 response. Nations that demonstrated EVD-related conditioned learning nations tended to have more stringent COVID-19 responses before April 2020 and utilized documented response mechanisms developed out of the West African crisis.


Subject(s)
COVID-19 , Hemorrhagic Fever, Ebola , Humans , COVID-19/epidemiology , COVID-19/prevention & control , Disease Outbreaks/prevention & control , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , Pandemics/prevention & control , Systems Analysis , World Health Organization
13.
Math Biosci Eng ; 20(11): 19686-19709, 2023 Oct 26.
Article in English | MEDLINE | ID: mdl-38052620

ABSTRACT

Past works on partially diffusive models of diseases typically rely on a strong assumption regarding the initial data of their infection-related compartments in order to demonstrate uniform persistence in the case that the basic reproduction number $ \mathcal{R}_0 $ is above 1. Such a model for avian influenza was proposed, and its uniform persistence was proven for the case $ \mathcal{R}_0 > 1 $ when all of the infected bird population, recovered bird population and virus concentration in water do not initially vanish. Similarly, a work regarding a model of the Ebola virus disease required that the infected human population does not initially vanish to show an analogous result. We introduce a modification on the standard method of proving uniform persistence, extending both of these results by weakening their respective assumptions to requiring that only one (rather than all) infection-related compartment is initially non-vanishing. That is, we show that, given $ \mathcal{R}_0 > 1 $, if either the infected bird population or the viral concentration are initially nonzero anywhere in the case of avian influenza, or if any of the infected human population, viral concentration or population of deceased individuals who are under care are initially nonzero anywhere in the case of the Ebola virus disease, then their respective models predict uniform persistence. The difficulty which we overcome here is the lack of diffusion, and hence the inability to apply the minimum principle, in the equations of the avian influenza virus concentration in water and of the population of the individuals deceased due to the Ebola virus disease who are still in the process of caring.


Subject(s)
Communicable Diseases , Hemorrhagic Fever, Ebola , Influenza A virus , Influenza in Birds , Influenza, Human , Animals , Humans , Influenza in Birds/epidemiology , Hemorrhagic Fever, Ebola/veterinary , Birds , Water , Influenza, Human/epidemiology
14.
Vopr Virusol ; 68(5): 372-384, 2023 Nov 07.
Article in Russian | MEDLINE | ID: mdl-38156572

ABSTRACT

RELEVANCE: Ebola virus disease (EVD) is an acute infectious disease with an extremely high case fatality rate reaching up to 90%. EVD has become widely known since 2014-2016, when outbreak in West Africa occurred and led to epidemic, which caused travel-related cases on the territory of other continents. There are two vaccines against EVD, prequalified by WHO for emergency use, as well as a number of vaccines, approved by local regulators in certain countries. However, even with the availability of effective vaccines, the lack of data on immune correlates of protection and duration of protective immune response in humans and primates is limiting factor for effectively preventing the spread of EVD outbreaks. AIMS: This review highlights experience of use of EVD vaccines during outbreaks in endemic areas, summarizes data on vaccine immunogenicity in clinical trials, and discusses perspectives for further development and use of effective EVD vaccines.


Subject(s)
Ebola Vaccines , Hemorrhagic Fever, Ebola , Animals , Humans , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , Travel , Travel-Related Illness , Disease Outbreaks/prevention & control
15.
Vaccine ; 41(50): 7573-7580, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-37981473

ABSTRACT

BACKGROUND: People living with HIV constitute an important part of the population in regions at risk of Ebola virus disease outbreaks. The two-dose Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen induces strong immune responses in HIV-positive (HIV+) adults but the durability of this response is unknown. It is also unclear whether this regimen can establish immune memory to enable an anamnestic response upon re-exposure to antigen. METHODS: This paper describes an open-label, phase 2 trial, conducted in Kenya and Uganda, of Ad26.ZEBOV booster vaccination in HIV+ participants who had previously received the Ad26.ZEBOV, MVA-BN-Filo primary regimen. HIV+ adults with well-controlled infection and on highly active antiretroviral therapy were enrolled, vaccinated with booster, and followed for 28 days. The primary objectives were to assess Ad26.ZEBOV booster safety and antibody responses against the Ebola virus glycoprotein using the Filovirus Animal Non-Clinical Group ELISA. RESULTS: The Ad26.ZEBOV booster was well-tolerated in HIV+ adults with mostly mild to moderate symptoms. No major safety concerns or serious adverse events were reported. Four and a half years after the primary regimen, 24/26 (92 %) participants were still classified as responders, with a pre-booster antibody geometric mean concentration (GMC) of 726 ELISA units (EU)/mL (95 %CI 447-1179). Seven days after the booster, the GMC increased 54-fold to 38,965 EU/mL (95 %CI 23532-64522). Twenty-one days after the booster, the GMC increased 176-fold to 127,959 EU/mL (95 %CI 93872-174422). The responder rate at both post-booster time points was 100 %. CONCLUSIONS: The Ad26.ZEBOV booster is safe and highly immunogenic in HIV+ adults with well-controlled infection. The Ad26.ZEBOV, MVA-BN-Filo regimen can generate long-term immune memory persisting for at least 4·5 years, resulting in a robust anamnestic response. TRIAL REGISTRATION: Pan African Clinical Trial Registry (PACTR202102747294430). CLINICALTRIALS: gov (NCT05064956).


Subject(s)
Ebola Vaccines , Ebolavirus , HIV Infections , Hemorrhagic Fever, Ebola , Adult , Humans , Antibodies, Viral , HIV , HIV Infections/drug therapy , Immunogenicity, Vaccine , Kenya , Uganda , Vaccinia virus
16.
Clin Case Rep ; 11(11): e8253, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38028078

ABSTRACT

Key Clinical Message: In the acute phase of Ebola virus disease (EVD) premature neonatal survival is extremely rare. High mortality is related to prematurity, neonatal complications of Ebola, and precarious conditions of neonatal care in underresourced ETUs. This is a case of preterm neonatal survival in the setting of acute maternal EVD infection. Abstract: This case describes rare preterm newborn survival in the setting of an Ebola treatment unit in Eastern DRC. The neonate was born vaginally to an acutely ill 17-year-old mother who was vaccinated against Ebola virus after being identified as a contact of her father, who was a confirmed case and who did not survive his infection. This woman was admitted to an Ebola treatment unit at 32 weeks of gestation and given monoclonal antibody treatment. She gave birth vaginally, succumbing to postpartum hemorrhage 14 h after delivery. This child survived despite compounding vulnerabilities of preterm birth and maternal Ebola infection. Despite a negative test for EVD, the neonate was given a single dose of monoclonal antibody therapy in the first days of life. We believe maternal vaccination and neonatal monoclonal antibody treatment contributed to the child's survival. The circumstances surrounding neonatal survival in this extremely resource-limited context must be analyzed and disseminated in order to increase rates of neonatal and maternal survival in future outbreaks. Maternal and neonatal health are critical aspects of outbreak response that have been understudied and underreported leaving clinicians severely underresourced to provide life-saving care in outbreak settings. Pregnancy and childbirth do not stop in times of disease outbreak, adequate equipment and trained staff required for quality neonatal care must be considered in future outbreak responses.

17.
BMC Public Health ; 23(1): 2362, 2023 11 29.
Article in English | MEDLINE | ID: mdl-38031082

ABSTRACT

BACKGROUND: Ebola virus disease is a medical condition whose consequent effects on quality of life of patients. In the history of infectious diseases, there have been pathologies that have had significant repercussions for caregivers, healthcare providers and the community. OBJECTIVES: This study investigate determinants of quality of life among caregivers of adolescent and young adult Ebola survivors in Democratic Republic of the Congo. METHODS: This was a cross sectional study. The study sites were the two health districts of Beni and Katwa, in North-Kivu province in the Eastern part of Democratic Republic of the Congo. The study period was from April to August 2022. Participants of the study were caregivers of adolescents and young adult Ebola virus survivors. Simple random sampling technique was used to select the 68 study participants. A questionnaire was administered. Data was collected using pretested questionnaire of WHO quality of life Bref (WHOQOL-BREF) and CommCare by Dimagi.Inc. lastest Version 2.52.1 and  a sum of score of 78 or higher indicated a high level of life quality. To determine the quality of life of caregivers of adolescents and young adult EVD survivors, descriptive analysis was used. The Pearson correlation coefficient was utilized to check whether the predictor variables are multicollinear. The regression analysis produced the crude odds ratio (COR), adjusted odds ratio (aOR), 95% confidence interval (CI), and p-value. Statistical significance was defined as a p-value 0.05. The final multivariate model contained variables that were significant in the bivariate analysis. Prior to data collection, a research permit from National Ethical Committee of Research in Democratic Republic of the Congo was obtained. Written informed consents from literate or illiterate caregivers of adolescent and young adult Ebola survivors were obtained. Throughout the study, participants' privacy and confidentiality were respected. RESULTS: A total of 68 care givers participated in the study, with a majority 54/68(79.41%) having poor quality of life. Men were 3.17 times more likely to record good quality of life than women (p = 0.02); OR:(95% CI), 3.17: (1.2 - 8.36), With regards to place of residence, caregivers who lived in town were less likely to have good quality of life compared to those in rural (p = 0.01); OR: (95%CI), 0.25: (0.09 - 0.72). CONCLUSION: The quality of life of caregivers of adolescent and young adult Ebola survivors in Democratic Republic of the Congo is poor. To be woman caregiver and to live in town are determinants associated with poor quality of life among caregivers of adolescent and young adult Ebola survivors.


Subject(s)
Hemorrhagic Fever, Ebola , Male , Humans , Adolescent , Female , Young Adult , Hemorrhagic Fever, Ebola/epidemiology , Cross-Sectional Studies , Caregivers , Quality of Life , Democratic Republic of the Congo , Survivors , Disease Outbreaks
18.
Vaccine ; 41(51): 7587-7597, 2023 Dec 12.
Article in English | MEDLINE | ID: mdl-37993355

ABSTRACT

Conducting a vaccine trial in a low- and middle-income country (LMIC) can present unique challenges and lessons learned. This Ebola vaccine trial, enrolling 699 healthcare providers and frontliners and jointly set up by the University of Antwerp (Sponsor) and the University of Kinshasa (Principal Investigator (PI)), was conducted in Boende, a remote city in the Democratic Republic of the Congo (DRC), between December 2019 and October 2022 (ClinicalTrials.gov: NCT04186000). While being bound by strict ICH-GCP and international funder regulations, this trial, exemplary for being a public-private partnership, required collaboration between several international stakeholders (e.g., two universities, a pharmaceutical company, and a clinical research organization), local communities and government agencies. Here we address several logistical and administrative challenges, cultural differences, language barriers and regulatory, political, and ethical considerations over the trial's 2.5-year duration, while tailoring and adapting the study to the specific local context. Lessons learned include the importance of clear communication with participants in all phases of the study, but also within the study team and among different stakeholders. Challenges, mitigations, and lessons learned are presented in nine categories (e.g., safety management; trial documentation, tools, and materials; communication, staff training and community engagement/sensitization; financial and administrative hurdles; and more). Ultimately, to reach the successful end of the vaccine trial in this remote Ebola endemic area in the DRC, careful planning, collaboration, and great flexibility and adaptability was often required from all involved partners. Despite the encountered challenges, the vaccine trial discussed in this paper was able to obtain high participant retention rates (i.e., 92% of participants completed the study). We hope that other international teams aspiring to conduct similar trials in remote areas of LMICs can learn from the way our challenges were addressed, mitigations developed, and lessons were learned.


Subject(s)
Ebola Vaccines , Hemorrhagic Fever, Ebola , Humans , Communication , Democratic Republic of the Congo/epidemiology , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , Universities , Clinical Trials as Topic
19.
Pan Afr Med J ; 45: 190, 2023.
Article in English | MEDLINE | ID: mdl-38020355

ABSTRACT

Introduction: the number of wild poliomyelitis cases, worldwide, dropped from 350,000 cases in 1988 to 33 in 2018. Acute flaccid paralysis (AFP) surveillance is a key strategy toward achieving global polio eradication. The 2014 Ebola virus disease (EVD) epidemic in West Africa infected over 28,000 people and had devastating effects on health systems in Guinea, Liberia, and Sierra Leone. We sought to assess the effects of the 2014 Ebola outbreak on AFP surveillance in Guinea and Liberia. Methods: a retrospective cross-sectional analysis was performed for Guinea and Liberia to evaluate EVD´s impact on World Health Organization (WHO) AFP surveillance performance indicators during 2012-2015. Results: both Guinea and Liberia met the WHO target non-polio AFP incidence rate nationally, and generally sub-nationally, prior to the EVD outbreak; rates decreased substantially during the outbreak in seven of eight regions in Guinea and 11 of 15 counties in Liberia. Throughout the study period, both Guinea and Liberia attained appropriate overall targets nationally for "notification" and "stool adequacy" indicators, but each country experienced periods of poor regional/county-specific indicator performance. Conclusion: these findings mirrored the negative effect of the Ebola outbreak on polio elimination activities in both countries and highlights the need to reinforce this surveillance system during times of crisis.


Subject(s)
Hemorrhagic Fever, Ebola , Poliomyelitis , Humans , Hemorrhagic Fever, Ebola/epidemiology , Liberia/epidemiology , Guinea/epidemiology , Retrospective Studies , Cross-Sectional Studies , alpha-Fetoproteins , Population Surveillance , Poliomyelitis/epidemiology , Poliomyelitis/prevention & control , Disease Outbreaks , Paralysis/epidemiology , Paralysis/etiology
20.
PLoS One ; 18(10): e0293077, 2023.
Article in English | MEDLINE | ID: mdl-37847703

ABSTRACT

BACKGROUND: No distinctive clinical signs of Ebola virus disease (EVD) have prompted the development of rapid screening tools or called for a new approach to screening suspected Ebola cases. New screening approaches require evidence of clinical benefit and economic efficiency. As of now, no evidence or defined algorithm exists. OBJECTIVE: To evaluate, from a healthcare perspective, the efficiency of incorporating Ebola prediction scores and rapid diagnostic tests into the EVD screening algorithm during an outbreak. METHODS: We collected data on rapid diagnostic tests (RDTs) and prediction scores' accuracy measurements, e.g., sensitivity and specificity, and the cost of case management and RDT screening in EVD suspect cases. The overall cost of healthcare services (PPE, procedure time, and standard-of-care (SOC) costs) per suspected patient and diagnostic confirmation of EVD were calculated. We also collected the EVD prevalence among suspects from the literature. We created an analytical decision model to assess the efficiency of eight screening strategies: 1) Screening suspect cases with the WHO case definition for Ebola suspects, 2) Screening suspect cases with the ECPS at -3 points of cut-off, 3) Screening suspect cases with the ECPS as a joint test, 4) Screening suspect cases with the ECPS as a conditional test, 5) Screening suspect cases with the WHO case definition, then QuickNavi™-Ebola RDT, 6) Screening suspect cases with the ECPS at -3 points of cut-off and QuickNavi™-Ebola RDT, 7) Screening suspect cases with the ECPS as a conditional test and QuickNavi™-Ebola RDT, and 8) Screening suspect cases with the ECPS as a joint test and QuickNavi™-Ebola RDT. We performed a cost-effectiveness analysis to identify an algorithm that minimizes the cost per patient correctly classified. We performed a one-way and probabilistic sensitivity analysis to test the robustness of our findings. RESULTS: Our analysis found dual ECPS as a conditional test with the QuickNavi™-Ebola RDT algorithm to be the most cost-effective screening algorithm for EVD, with an effectiveness of 0.86. The cost-effectiveness ratio was 106.7 USD per patient correctly classified. The following algorithms, the ECPS as a conditional test with an effectiveness of 0.80 and an efficiency of 111.5 USD per patient correctly classified and the ECPS as a joint test with the QuickNavi™-Ebola RDT algorithm with an effectiveness of 0.81 and a cost-effectiveness ratio of 131.5 USD per patient correctly classified. These findings were sensitive to variations in the prevalence of EVD in suspected population and the sensitivity of the QuickNavi™-Ebola RDT. CONCLUSIONS: Findings from this study showed that prediction scores and RDT could improve Ebola screening. The use of the ECPS as a conditional test algorithm and the dual ECPS as a conditional test and then the QuickNavi™-Ebola RDT algorithm are the best screening choices because they are more efficient and lower the number of confirmation tests and overall care costs during an EBOV epidemic.


Subject(s)
Hemorrhagic Fever, Ebola , Humans , Hemorrhagic Fever, Ebola/diagnosis , Hemorrhagic Fever, Ebola/epidemiology , Cost-Benefit Analysis , Rapid Diagnostic Tests , Sensitivity and Specificity , Algorithms , Diagnostic Tests, Routine/methods
SELECTION OF CITATIONS
SEARCH DETAIL
...