Clinical features of suspected Ebola cases referred to the Moyamba ETC, Sierra Leone: challenges in the later stages of the 2014 outbreak

Association between oral antimalarial medication administration and mortality among patients with Ebola virus disease: a multisite cohort study

BACKGROUND

Empiric antimalarial treatment is a component of protocol-based management of Ebola virus disease (EVD), yet this approach has limited clinical evidence for patient-centered benefits.

METHODS

This retrospective cohort study evaluated the association between antimalarial treatment and mortality among patients with confirmed EVD. The data was collected from five International Medical Corps operated Ebola Treatment Units (ETUs) in Sierra Leone and Liberia from 2014 through 2015. The standardized protocol used for patient care included empiric oral treatment with combination artemether and lumefantrine, twice daily for three days; however, only a subset of patients received treatment due to resource variability. The outcome of interest was mortality, comparing patients treated with oral antimalarials within 48-h of admission to those not treated. Analysis was conducted with logistic regression to generate adjusted odds ratios (aORs). Multivariable analyses controlled for ETU country, malaria rapid diagnostic test result, age, EVD cycle threshold value, symptoms of bleeding, diarrhea, dysphagia and dyspnea, and additional standard clinical treatments.

RESULTS

Among the 424 cases analyzed, 376 (88.7%) received early oral antimalarials. Across all cases, mortality occurred in 57.5% (244). In comparing unadjusted mortality prevalence, early antimalarial treated cases yielded 55.1% mortality versus 77.1% mortality for those untreated (p = 0.005). Multivariable analysis demonstrated evidence of reduced aOR for mortality with early oral antimalarial treatment versus non-treatment (aOR = 0.34, 95% Confidence Interval: 0.12, 0.92, p = 0.039).

CONCLUSION

Early oral antimalarial treatment in an EVD outbreak was associated with reduced mortality. Further study is warranted to investigate this association between early oral antimalarial treatment and mortality in EVD patients.

Building the Sierra Leone Ebola Database: organization and characteristics of data systematically collected during 2014-2015 Ebola epidemic

PURPOSE

During the 2014-2016 Ebola outbreak in West Africa, the Sierra Leone Ministry of Health and Sanitation (MoHS), the US Centers for Disease Control and Prevention, and responding partners under the coordination of the National Ebola Response Center (NERC) and the MoHS's Emergency Operation Center (EOC) systematically recorded information from the 117 Call Center system and district alert phone lines, case investigations, laboratory sample testing, clinical management, and safe and dignified burial records. Since 2017, CDC assisted MoHS in building and managing the Sierra Leone Ebola Database (SLED) to consolidate these major data sources. The primary objectives of the project were helping families to identify the location of graves of their loved ones who died at the time of the Ebola epidemic through the SLED Family Reunification Program and creating a data source for epidemiological research. The objective of this paper is to describe the process of consolidating epidemic records into a useful and accessible data collection and to summarize data characteristics, strength, and limitations of this unique information source for public health research.

METHODS

Because of the unprecedented conditions during the epidemic, most of the records collected from responding organizations required extensive processing before they could be used as a data source for research or the humanitarian purpose of locating burial sites. This process required understanding how the data were collected and used during the outbreak. To manage the complexity of processing the data obtained from various sources, the Sierra Leone Ebola Database (SLED) Team used an organizational strategy that allowed tracking of the data provenance and lifecycle.

RESULTS

The SLED project brought raw data into one consolidated data collection. It provides researchers with secure and ethical access to the SLED data and serves as a basis for the research capacity building in Sierra Leone. The SLED Family Reunification Program allowed Sierra Leonean families to identify location of the graves of loved ones who died during the Ebola epidemic.

CONCLUSIONS

The SLED project consolidated and utilized epidemic data recorded during the Sierra Leone Ebola Virus Disease outbreak that were collected and contributed to SLED by national and international organizations. This project has provided a foundation for developing a method of ethical and secure SLED data access while preserving the host nation's data ownership. SLED serves as a data source for the SLED Family Reunification Program and for epidemiological research. It presents an opportunity for building research capacity in Sierra Leone and provides a foundation for developing a relational database. Large outbreak data systems such as SLED provide a unique opportunity for researchers to improve responses to epidemics and indicate the need to include data management preparedness in the plans for emergency response.

Meta-analysis of predictive symptoms for Ebola virus disease

INTRODUCTION

One of the leading challenges in the 2013-2016 West African Ebola virus disease (EVD) outbreak was how best to quickly identify patients with EVD, separating them from those without the disease, in order to maximise limited isolation bed capacity and keep health systems functioning.

METHODOLOGY

We performed a systematic literature review to identify all published data on EVD clinical symptoms in adult patients. Data was dual extracted, and random effects meta-analysis performed for each symptom to identify symptoms with the greatest risk for EVD infection.

RESULTS

Symptoms usually presenting late in illness that were more than twice as likely to predict a diagnosis of Ebola, were confusion (pOR 3.04, 95% CI 2.18-4.23), conjunctivitis (2.90, 1.92-4.38), dysphagia (1.95, 1.13-3.35) and jaundice (1.86, 1.20-2.88). Early non-specific symptoms of diarrhoea (2.99, 2.00-4.48), fatigue (2.77, 1.59-4.81), vomiting (2.69, 1.76-4.10), fever (1.97, 1.10-4.52), muscle pain (1.65, 1.04-2.61), and cough (1.63, 1.24-2.14), were also strongly associated with EVD diagnosis.

CONCLUSIONS

The existing literature fails to provide a unified position on the symptoms most predictive of EVD, but highlights some early and late stage symptoms that in combination will be useful for future risk stratification. Confirmation of these findings across datasets (or ideally an aggregation of all individual patient data) will aid effective future clinical assessment, risk stratification tools and emergency epidemic response planning.

A Modified Case Definition to Facilitate Essential Hospital Care During Ebola Outbreaks

During the late phase of the large West-African Ebola virus disease (EVD) outbreak, the majority of patients were cared for in designated treatment centers. However, the preexisting healthcare infrastructure was already overwhelmed by the outbreak. This had a huge impact on other, non-EVD-related diseases, causing an unprecedented increase in morbidity and mortality, which most likely exceeded the toll due to EVD directly. Consequently, a crucial question is how to provide appropriate healthcare and safeguard functionality of a healthcare system that also serves patients not suspected or diagnosed to have EVD. Here, we report on the Lion Heart Medical Center's experience in Sierra Leone and note that a case definition of Ebola that is broader than those commonly applied may be better suited when it is necessary to identify atypically presenting, pauci-symptomatic cases.

Clinical and epidemiological performance of WHO Ebola case definitions: a systematic review and meta-analysis

BACKGROUND

Ebola virus disease case definition is a crucial surveillance tool to detect suspected cases for referral and as a screening tool for clinicians to support admission and laboratory testing decisions at Ebola health facilities. We aimed to assess the performance of the WHO Ebola virus disease case definitions and other screening scores.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Scopus, Embase, and Web of Science for studies published in English between June 13, 1978, and Jan 14, 2020. We included studies that estimated the sensitivity and specificity of WHO Ebola virus disease case definitions, clinical and epidemiological characteristics (symptoms at admission and contact history), and predictive risk scores against the reference standard (laboratory-confirmed Ebola virus disease). Summary estimates of sensitivity and specificity were calculated using bivariate and hierarchical summary receiver operating characteristic (when four or more studies provided data) or random-effects meta-analysis (fewer than four studies provided data).

FINDINGS

We identified 2493 publications, of which 14 studies from four countries (Sierra Leone, Guinea, Liberia, and Angola) were included in the analysis. 12 021 people with suspected disease were included, of whom 4874 were confirmed as positive for Ebola virus infection. Six studies explored the performance of WHO case definitions in non-paediatric populations, and in all of these studies, suspected and probable cases were combined and could not be disaggregated for analysis. The pooled sensitivity of the WHO Ebola virus disease case definitions from these studies was 81·5% (95% CI 74·1-87·2) and pooled specificity was 35·7% (28·5-43·6). History of contact or epidemiological link was a key predictor for the WHO case definitions (seven studies) and for risk scores (six studies). The most sensitive symptom was intense fatigue (79·0% [95% CI 74·4-83·0]), assessed in seven studies, and the least sensitive symptom was pain behind the eyes (1·0% [0·0-7·0]), assessed in three studies. The performance of fever as a symptom varied depending on the cutoff used to define fever.

INTERPRETATION

WHO Ebola virus disease case definitions perform suboptimally to identify cases at both community level and during triage at Ebola health facilities. Inclusion of intense fatigue as a key symptom and contact history could improve the performance of case definitions, but implementation of these changes will require effective collaboration with, and trust of, affected communities.

FUNDING

Médecins sans Frontières.

A systematic review and meta-analysis of patient data from the West Africa (2013-16) Ebola virus disease epidemic

BACKGROUND

Over 28 000 individuals were infected with Ebola virus during the West Africa (2013-2016) epidemic, yet there has been criticism of the lack of robust clinical descriptions of Ebola virus disease (EVD) illness from that outbreak.

OBJECTIVES

To perform a meta-analysis of published data from the epidemic to describe the clinical presentation, evolution of disease, and predictors of mortality in individuals with EVD. To assess the quality and utility of published data for clinical and public health decision-making.

DATA SOURCES

Primary articles available in PubMed and published between January 2014 and May 2017.

ELIGIBILITY

Studies that sequentially enrolled individuals hospitalized for EVD and that reported acute clinical outcomes.

METHODS

We performed meta-analyses using random-effect models and assessed heterogeneity using the I2 method. We assessed data representativeness by comparing meta-analysis estimates with WHO aggregate data. We examined data utility by examining the availability and compatibility of data sets.

RESULTS

In all, 3653 articles were screened and 34 articles were included, representing 16 independent cohorts of patients (18 overlapping cohorts) and at least 6168 individuals. The pooled estimate for case fatality rate was 51% (95% CI 46%-56%). However, pooling of estimates for clinical presentation, progression, and predictors of mortality in individuals with EVD were hampered by significant heterogeneity, and inadequate data on clinical progression. Our assessment of data quality found that heterogeneity was largely unexplained, and data availability and compatibility were poor.

CONCLUSIONS

We have quantified a missed opportunity to generate reliable estimates of the clinical manifestations of EVD during the West Africa epidemic. Clinical data standards and data capture platforms are urgently needed.

Reporting quality of the 2014 Ebola outbreak in Africa: A systematic analysis

The objective of this study was to conduct a systematic analysis of the reporting quality of the Ebola Virus Disease (EVD) outbreak in West Africa from 2014-2018 using the Modified STROBE statement. We included studies on the 2014 EVD outbreak alone, limited to those on human patients in Africa. We searched the following databases (MEDLINE, EMBASE, and Web of Science) for outbreak reports published between 2014-2018. We assessed factors potentially associated with the quality of reporting. A total of 69 of 131 (53%) articles within the full-text review fulfilled our eligibility criteria and underwent the Modified STROBE assessment for analyzing the quality of reporting. The Modified STROBE scores of the included studies ranged from 11-26 points and the mean was found to be 19.54 out of 30 with a standard deviation (SD) of ± 4.30. The top three reported Modified STROBE components were descriptive characteristics of study participants, scientific background and evidence rational, and clinical significance of observations. More than 75% of the studies met a majority of the criteria in the Modified STROBE assessment tool. Information that was commonly missing included addressing potential source of bias, sensitivity analysis, further results/analysis such as risk estimates and odds ratios, presence of a flowchart, and addressing missing data. In multivariable analysis, peer-reviewed publication was the only predictor that remained significantly associated with a higher Modified STROBE score. In conclusion, the large range of Modified STROBE scores observed indicates variability in the quality of outbreak reports for EVD. The review identified strong reporting in some areas, whereas other areas are in need of improvement, in particular providing an important description of the outbreak setting and identifying any external elements (potential biases and confounding factors) that could hinder the credibility of the findings.

HIV prevalence in suspected Ebola cases during the 2014-2016 Ebola epidemic in Sierra Leone

BACKGROUND

The 2014-2016 Ebola virus epidemic in West Africa was the largest outbreak of Ebola virus disease (EVD) in history. Clarifying the influence of other prevalent diseases such as human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV/AIDS) will help improve treatment and supportive care of patients with EVD.

CASE PRESENTATION

We examined HIV and hepatitis C virus (HCV) antibody prevalence among suspected EVD cases from the Sierra Leone-China Friendship Biological Safety Laboratory during the epidemic in Sierra Leone. HIV and HCV antibodies were tested in 678 EVD-negative samples by enzyme-linked immunosorbent assay. A high HIV prevalence (17.6%) and low HCV prevalence (0.22%) were observed among the suspected cases. Notably, we found decreased HIV positive rates among the suspected cases over the course of the epidemic. This suggests a potentially beneficial effect of an improved public health system after assistance from the World Health Organization and other international aid organizations.

CONCLUSIONS

This EVD epidemic had a considerable impact on the public health system and influenced the prevalence of HIV found among suspected cases in Sierra Leone, but also provided an opportunity to establish a better surveillance network for infectious diseases.

Development of a Pediatric Ebola Predictive Score, Sierra Leone1

We compared children who were positive for Ebola virus disease (EVD) with those who were negative to derive a pediatric EVD predictor (PEP) score. We collected data on all children <13 years of age admitted to 11 Ebola holding units in Sierra Leone during August 2014–March 2015 and performed multivariable logistic regression. Among 1,054 children, 309 (29%) were EVD positive and 697 (66%) EVD negative, with 48 (5%) missing. Contact history, conjunctivitis, and age were the strongest positive predictors for EVD. The PEP score had an area under receiver operating characteristics curve of 0.80. A PEP score of 7/10 was 92% specific and 44% sensitive; 3/10 was 30% specific, 94% sensitive. The PEP score could correctly classify 79%–90% of children and could be used to facilitate triage into risk categories, depending on the sensitivity or specificity required.

Sensitivity and Specificity of Suspected Case Definition Used during West Africa Ebola Epidemic

Rapid early detection and control of Ebola virus disease (EVD) is contingent on accurate case definitions. Using an epidemic surveillance dataset from Guinea, we analyzed an EVD case definition developed by the World Health Organization (WHO) and used in Guinea. We used the surveillance dataset (March-October 2014; n = 2,847 persons) to identify patients who satisfied or did not satisfy case definition criteria. Laboratory confirmation determined cases from noncases, and we calculated sensitivity, specificity and predictive values. The sensitivity of the defintion was 68.9%, and the specificity of the definition was 49.6%. The presence of epidemiologic risk factors (i.e., recent contact with a known or suspected EVD case-patient) had the highest sensitivity (74.7%), and unexplained deaths had the highest specificity (92.8%). Results for case definition analyses were statistically significant (p<0.05 by χ² test). Multiple components of the EVD case definition used in Guinea contributed to improved overall sensitivity and specificity.