Representations of an Ebola 'outbreak' through Story Technologies

BACKGROUND

Attempts to understand biosocial phenomena using scientific methods are often presented as value-neutral and objective; however, when used to reduce the complexity of open systems such as epidemics, these forms of inquiry necessarily entail normative considerations and are therefore fashioned by political worldviews (ideologies). From the standpoint of poststructural theory, the character of these representations is at most limited and partial. In addition, these modes of representation (as stories) do work (as technologies) in the service of, or in resistance to, power.

METHODS

We focus on a single Ebola case cluster from the 2013-2016 outbreak in West Africa and examine how different disciplinary forms of knowledge production (including outbreak forecasting, active epidemiological surveillance, post-outbreak serosurveys, political economic analyses, and ethnography) function as Story Technologies. We then explore how these technologies are used to curate 'data,' analysing the erasures, values, and imperatives evoked by each.

RESULTS

We call attention to the instrumental-in addition to the descriptive-role Story Technologies play in ordering contingencies and establishing relationships in the wake of health crises.

DISCUSSION

By connecting each type of knowledge production with the systems of power it reinforces or disrupts, we illustrate how Story Technologies do ideological work. These findings encourage research from pluriversal perspectives and advocacy for measures that promote more inclusive modes of knowledge production.

The effect of Mediterranean diet on inflammatory biomarkers and components of metabolic syndrome in adolescent girls

BACKGROUND

The prevalence of obesity and metabolic syndrome (MetS) during childhood and adolescence is rising significantly worldwide. Previous studies have shown that following a healthy dietary pattern, like the Mediterranean diet (MD), might be an efficacious approach for the prevention and management of MetS during childhood. In the present study, we aimed to examine the effect of MD on inflammatory markers and components of MetS among adolescent girls with MetS.

METHODS

This randomized controlled clinical trial was conducted on 70 girl adolescents with metabolic syndrome. Patients in the intervention group followed a prescribed MD, while participants in the control group received dietary advice according to the food pyramid. The length of intervention was 12 weeks. Participants' dietary intakes were evaluated using three 1-day food records throughout the study. Anthropometric measures, inflammatory markers, systolic and diastolic blood pressure, and hematological factors were assessed at the baseline and end of the trial. An intention-to-treat approach was taken into account for the statistical analysis.

RESULTS

After 12 weeks, participants in the intervention group had lower weight (Ptime*group ≤ 0/001), body mass index (BMI) (Ptime*group ≤ 0/001), and waist circumference (WC) (Ptime*group ≤ 0/001) compared with those in the control group. In addition, MD resulted in a significantly reduced systolic blood pressure compared to the those in the control group (Ptime*group ≤ 0/001). In terms of metabolic variables, MD led to a significant decrease in fasting blood glucose (FBS) (Ptime*group ≤ 0/001), triglycerides (TG) (Ptime*group ≤ 0/001), low-density lipoprotein (LDL) (Ptime*group ≤ 0/001), homeostatic model assessment of insulin resistance (HOMA-IR) (Ptime*group = 0/02) and a meaningful increase in serum levels of high-density lipoprotein (HDL) (Ptime*group ≤ 0/001). In addition, adherence to the MD resulted in a significant reduction in serum levels of inflammatory markers including Interleukin 6 (IL-6) (Ptime*group = 0/02) and high-sensitivity C-reactive protein (hs-CRP) (Ptime*group = 0/02). However, no significant effect was seen on serum levels of tumor necrosis factor α (TNF-α) (Ptime*group = 0/43).

CONCLUSION

Overall, the findings of the present study revealed that consumption of MD for 12 weeks resulted in a favorable effect on anthropometric measures, components of MetS, as well as on some inflammatory biomarkers.

Simplifying the estimation of diagnostic testing accuracy over time for high specificity tests in the absence of a gold standard

Many different methods for evaluating diagnostic test results in the absence of a gold standard have been proposed. In this paper, we discuss how one common method, a maximum likelihood estimate for a latent class model found via the Expectation-Maximization (EM) algorithm can be applied to longitudinal data where test sensitivity changes over time. We also propose two simplified and nonparametric methods which use data-based indicator variables for disease status and compare their accuracy to the maximum likelihood estimation (MLE) results. We find that with high specificity tests, the performance of simpler approximations may be just as high as the MLE.

Contextualizing mobility during the Ebola epidemic in Liberia

Based on findings from focus groups and key informant interviews conducted at five sites in Liberia between 2018 and 2019, we explore some of the key factors that influenced people's motivation to travel during the 2014-2016 Ebola Virus Disease (EVD). We discuss how these factors led to certain mobility patterns and the implications these had for EVD response. The reasons for individual mobility during the epidemic were multiple and diverse. Some movements were related to relocation efforts as people attempted to extricate themselves from stigmatizing situations. Others were motivated by fear, convinced that other communities would be safer, particularly if extended family members resided there. Individuals also felt compelled to travel during the epidemic to meet other needs and obligations, such as attending burial rites. Some expressed concerns about obtaining food and earning a livelihood. Notably, these latter concerns served as an impetus to travel surreptitiously to evade quarantine directives aimed specifically at restricting mobility. Improvements in future infectious disease response could be made by incorporating contextually-based mobility factors, for example: the personalization of public health messaging through the recruitment of family members and trusted local leaders, to convey information that would help allay fear and combat stigmatization; activating existing traditional community surveillance systems in which entry into the community must first be approved by the community chief; and increased involvement of local leaders and community members in the provision of food and care to those quarantined so that the need to travel for these reasons is removed.

Health Management Workforce Capacity-Building in Liberia, Post-Ebola

Following the Ebola crisis in Liberia in 2014-15, the Liberian Ministry of Health developed a strategy to build a fit-for-purpose health workforce, focusing on both health care providers and health managers. To help fulfill national capacity-building goals for health management, a team of faculty, staff, and practitioners from the Yale School of Medicine, the University of Liberia, the National Public Health Institute of Liberia, and the Ministry of Health collaboratively developed and launched the health management program in Liberia in July 2017. The team worked to build specific management and leadership competencies for healthcare workers serving in management and leadership roles in Liberia's health sector using two concurrent strategies-1) implementation of a hospital-based partnership-mentorship model in the two largest hospitals in the capital city of Monrovia, and 2) establishment of an executive education-style advanced Certificate in Health Systems Leadership and Management at the University of Liberia. Here we describe the health management program in Liberia, its focus, and its evolution from program launch in 2017 to the present, as well as ongoing efforts to transition program activities to local partner ownership by the end of 2021.

The impact of the 2014 Ebola epidemic on HIV disease burden and outcomes in Liberia West Africa

BACKGROUND

Detailed longitudinal studies of HIV-positive individuals in West Africa are lacking. Here the HIV prevalence, incidence, all-cause mortality, and the proportion of individuals receiving treatment with cART in two cohorts of participants in Ebola-related studies are described.

SETTING

Individuals of all ages were enrolled and followed at four sites in the area of Monrovia, Liberia.

METHODS

Two cohorts identified in response to the Ebola epidemic are described to provide insights into the current state of the HIV epidemic. HIV testing was performed at baseline for participants in both cohorts and during follow-up in one cohort.

RESULTS

Prevalence and incidence of HIV (prevalence of 3.1% for women and 1.4% for men and incidence of 3.3 per 1,000) were higher in these cohorts compared to 2018 national estimates (prevalence of 1.3% and incidence of 0.39 per 1,000). Most participants testing positive did not know their status prior to testing. Of those who knew they were HIV positive, 7.9% reported being on antiretroviral treatment. The death rate among those with HIV was 12.3% compared to 1.9% in HIV-negative individuals (adjusted odds ratio of 6.87). While higher levels of d-dimer were associated with increased mortality, this was not specific to those with HIV, however lower hemoglobin levels were associated with increased mortality among those with HIV.

CONCLUSION

These findings point to a need to perform further research studies aimed at fulfilling these knowledge gaps and address current shortcomings in the provision of care for those living with HIV in Liberia.

A framework for scabies control

Scabies is a neglected tropical disease (NTD) that causes a significant health burden, particularly in disadvantaged communities and where there is overcrowding. There is emerging evidence that ivermectin-based mass drug administration (MDA) can reduce the prevalence of scabies in some settings, but evidence remains limited, and there are no formal guidelines to inform control efforts. An informal World Health Organization (WHO) consultation was organized to find agreement on strategies for global control. The consultation resulted in a framework for scabies control and recommendations for mapping of disease burden, delivery of interventions, and establishing monitoring and evaluation. Key operational research priorities were identified. This framework will allow countries to set control targets for scabies as part of national NTD strategic plans and develop control strategies using MDA for high-prevalence regions and outbreak situations. As further evidence and experience are collected and strategies are refined over time, formal guidelines can be developed. The control of scabies and the reduction of the health burden of scabies and associated conditions will be vital to achieving the targets set in WHO Roadmap for NTDs for 2021 to 2030 and the Sustainable Development Goals.

Increased Likelihood of Detecting Ebola Virus RNA in Semen by Using Sample Pelleting

Ebola virus RNA can reside for months or years in semen of survivors of Ebola virus disease and is probably associated with increased risk for cryptic sexual transmission of the virus. A modified protocol resulted in increased detection of Ebola virus RNA in semen and improved disease surveillance.

Community engagement for health system resilience: evidence from Liberia's Ebola epidemic

The importance of community engagement (CE) for health system resilience is established in theoretical and empirical literature. The practical dimensions of how to operationalize theory and implement its principles have been less explored, especially within low-resource crisis settings. It is therefore unclear how CE is drawn upon and how, if at all, it facilitates health system resilience in times of health system crises. To address this critical gap, we adapt and apply existing theoretical CE frameworks to analyse qualitative data from 92 in-depth interviews and 16 focus group discussions collected with health system stakeholders in Liberia in the aftermath of the 2014-15 Ebola outbreak. Health system stakeholders indicated that CE was a crucial contributing factor in addressing the Ebola epidemic in Liberia. Multiple forms of CE were used during the outbreak; however, only some forms were perceived as meaningful, such as the formation of community-based surveillance teams. To achieve meaningful CE, participants recommended that communities be treated as active participants in-as opposed to passive recipients of-health response efforts and that communication platforms for CE be established ahead of a crisis. Participant responses highlight that meaningful CE led to improved communication with and increased trust in health authorities and programming. This facilitated health system response efforts, leading to a fortuitous cycle of increased trust, improved communication and continued meaningful CE-all necessary conditions for health system resilience. This study refines our understanding of CE and demonstrates the ways in which meaningful CE and trust work together in mutually reinforcing and beneficial ways. These findings provide empirical evidence on which to base policies and programmes aimed at improving health system resilience in low-resource settings to more effectively respond to health system crises.

A community-based validation of the International Alliance for the Control of Scabies Consensus Criteria by expert and non-expert examiners in Liberia

Background

The International Alliance for the Control of Scabies (IACS) recently published expert consensus criteria for scabies diagnosis. Formal validation of these criteria is needed to guide implementation. We conducted a study to provide detailed description of the morphology and distribution of scabies lesions as assessed by dermatologists and validate the IACS criteria for diagnosis by both expert and non-expert examiners.

Methods

Participants from a community in Monrovia, Liberia, were independently assessed by two dermatologists and six non-expert examiners. Lesion morphology and distribution were documented based on the dermatologist examination. Diagnoses were classified by IACS criteria and the sensitivity and specificity of non-expert examiner assessments calculated.

Results

Papules were the most common lesions (97.8%). Burrows were found in just under half (46.7%) and dermatoscopy was positive in a minority (13.3%). Scabies lesions were found in all body regions but more than 90% of patients could have been diagnosed by an examination of only the limbs. Severity of itch was associated with lesion number (p = 0.003). The sensitivity of non-expert examiners to detect typical scabies ranged between 69–83% and specificity 70–96%. The sensitivity of non-expert examiners was higher in more extensive disease (78–94%).

Conclusions

The IACS criteria proved a valid tool for scabies diagnosis. For the purposes of implementation papules and burrows represent truly ‘typical’ scabies lesions.

Non-expert examiners are able to diagnose scabies with a high degree of accuracy, demonstrating they could form a key component in population-level control strategies.

Scabies is a very common skin condition in both high- and low-income settings with hundreds of millions of people affected each year. Recently standardised criteria have been proposed to help improve the quality of scabies diagnosis, in particular in low income settings where the access to a skin specialist is very limited.

In this study, conducted in Liberia, expert examiners conducted a thorough examination and recorded what different types of skin problems they found in participants with and without scabies. We then compared the accuracy of a diagnosis of scabies made by dermatologists to that made by non-specialist healthcare workers who had received a short training course over three days.

We found that papules were the most common type of scabies lesion and were found in almost every single patient with scabies. A second type of skin lesion called a burrow was the next most common and was found in just under half of the participants. Other types of scabies lesions which have been described were rare in this study. We found that after the short training course the non-specialists were able to detect the majority of the cases of scabies correctly.

Our study has helped provide detailed data on exactly what types of skin changes are typical of scabies and demonstrated how short training programmes can help improve the skill of non-specialist examiners in diagnosing scabies.

Lassa virus circulating in Liberia: a retrospective genomic characterisation

BACKGROUND

An alarming rise in reported Lassa fever cases continues in west Africa. Liberia has the largest reported per capita incidence of Lassa fever cases in the region, but genomic information on the circulating strains is scarce. The aim of this study was to substantially increase the available pool of data to help foster the generation of targeted diagnostics and therapeutics.

METHODS

Clinical serum samples collected from 17 positive Lassa fever cases originating from Liberia (16 cases) and Guinea (one case) within the past decade were processed at the Liberian Institute for Biomedical Research using a targeted-enrichment sequencing approach, producing 17 near-complete genomes. An additional 17 Lassa virus sequences (two from Guinea, seven from Liberia, four from Nigeria, and four from Sierra Leone) were generated from viral stocks at the US Centers for Disease Control and Prevention (Atlanta, GA) from samples originating from the Mano River Union (Guinea, Liberia, and Sierra Leone) region and Nigeria. Sequences were compared with existing Lassa virus genomes and published Lassa virus assays.

FINDINGS

The 23 new Liberian Lassa virus genomes grouped within two clades (IV.A and IV.B) and were genetically divergent from those circulating elsewhere in west Africa. A time-calibrated phylogeographic analysis incorporating the new genomes suggests Liberia was the entry point of Lassa virus into the Mano River Union region and estimates the introduction to have occurred between 300-350 years ago. A high level of diversity exists between the Liberian Lassa virus genomes. Nucleotide percent difference between Liberian Lassa virus genomes ranged up to 27% in the L segment and 18% in the S segment. The commonly used Lassa Josiah-MGB assay was up to 25% divergent across the target sites when aligned to the Liberian Lassa virus genomes.

INTERPRETATION

The large amount of novel genomic diversity of Lassa virus observed in the Liberian cases emphasises the need to match deployed diagnostic capabilities with locally circulating strains and underscores the importance of evaluating cross-lineage protection in the development of vaccines and therapeutics.

FUNDING

Defense Biological Product Assurance Office of the US Department of Defense and the Armed Forces Health Surveillance Branch and its Global Emerging Infections Surveillance and Response Section.

Lessons learned from detecting and responding to recurrent measles outbreak in Liberia post Ebola-Epidemic 2016-2017

Introduction

Measles is an acute viral disease that remains endemic in much of sub-Sahara Africa, including Liberia. The 2014 Ebola epidemic disrupted an already fragile health system contributing to low uptake of immunization services, population immunity remained low thus facilitating recurrent outbreaks of measles in Liberia. We describe lessons learnt from detecting and responding to recurrent outbreaks of measles two years post the 2014 Ebola epidemic in Liberia.

Methods

We conducted a descriptive study using the findings from Integrated Diseases Surveillance and Response (IDSR) 15 counties, National Public Health Institute of Liberia (NPHIL), National Public Health Reference Laboratory (NPHRL) and District Health Information Software (DIHS2) data conducted from October to December, 2017. We perused the outbreaks line lists and other key documents submitted by the counties to the national level from January 2016 to December 2017.

Results

From January 2016 to December 2017, 2,954 suspected cases of measles were reported through IDSR. Four hundred sixty-seven (467) were laboratory confirmed (IgM-positive), 776 epidemiologically linked, 574 clinically confirmed, and 1,137 discarded (IgM-negative). Nine deaths out of 1817 cases were reported, a case fatality rate of 0.5%; 49% were children below the age of 5 years. Twenty-two percent (405/1817) of the confirmed cases were vaccinated while the vaccination status of 55% (994/1817) was unknown.

Conclusion

Revitalization of IDSR contributed to increased detection and reporting of suspected cases of measles thus facilitating early identification and response to outbreaks. Priority needs to be given to increasing the uptake of routine immunization services, introducing a second dose of measles vaccine in the routine immunization program and conducting a high-quality supplementary measles immunization campaign for age group 1 to 10 years to provide protection for a huge cohort of susceptible.

Use of the Filovirus Animal Non-Clinical Group (FANG) Ebola virus immuno-assay requires fewer study participants to power a study than the Alpha Diagnostic International assay

As part of the scientific community's development of medical countermeasures against Ebola virus disease, optimization of standardized assays for product evaluation is paramount. The recent outbreak heightened awareness to the scarcity of available assays and limited information on performance and reproducibility. To evaluate the immunogenicity of vaccines entering Phase I-III trials and to identify survivors, two enzyme-linked immunosorbent assays, the Filovirus Animal Non-Clinical Group assay and the Alpha Diagnostics International assay, were evaluated for detection of immunoglobulin G against Ebola virus glycoprotein. We found that the Filovirus Animal Nonclinical Group assay produced a wider range of relative antibody concentrations, higher assay precision, larger relative accuracy range, and lower regional background. Additionally, to sufficiently power a vaccine trial, use of the Filovirus Animal Nonclinical Group assay would require one third the number of participants than the Alpha Diagnostics International assay. This reduction in needed study participants will require less money, fewer man hours, and much less time to evaluate vaccine immunogenicity.

Ring vaccination with rVSV-ZEBOV under expanded access in response to an outbreak of Ebola virus disease in Guinea, 2016: an operational and vaccine safety report

Background

In March, 2016, a flare-up of Ebola virus disease was reported in Guinea, and in response ring vaccination with the unlicensed rVSV-ZEBOV vaccine was introduced under expanded access, the first time that an Ebola vaccine has been used in an outbreak setting outside a clinical trial. Here we describe the safety of rVSV-ZEBOV candidate vaccine and operational feasibility of ring vaccination as a reactive strategy in a resource-limited rural setting.

Methods

Approval for expanded access and compassionate use was rapidly sought and obtained from relevant authorities. Vaccination teams and frozen vaccine were flown to the outbreak settings. Rings of contacts and contacts of contacts were defined and eligible individuals, who had given informed consent, were vaccinated and followed up for 21 days under good clinical practice conditions.

Findings

Between March 17 and April 21, 2016, 1510 individuals were vaccinated in four rings in Guinea, including 303 individuals aged between 6 years and 17 years and 307 front-line workers. It took 10 days to vaccinate the first participant following the confirmation of the first case of Ebola virus disease. No secondary cases of Ebola virus disease occurred among the vaccinees. Adverse events following vaccination were reported in 47 (17%) 6–17 year olds (all mild) and 412 (36%) adults (individuals older than 18 years; 98% were mild). Children reported fewer arthralgia events than adults (one [<1%] of 303 children vs 81 [7%] of 1207 adults). No severe vaccine-related adverse events were reported.

Interpretation

The results show that a ring vaccination strategy can be rapidly and safely implemented at scale in response to Ebola virus disease outbreaks in rural settings.

Funding

WHO, Gavi, and the World Food Programme.

Analysis of patient data from laboratories during the Ebola virus disease outbreak in Liberia, April 2014 to March 2015

An outbreak of Ebola virus disease (EVD) in Liberia began in March 2014 and ended in January 2016. Epidemiological information on the EVD cases was collected and managed nationally; however, collection and management of the data were challenging at the time because surveillance and reporting systems malfunctioned during the outbreak. EVD diagnostic laboratories, however, were able to register basic demographic and clinical information of patients more systematically. Here we present data on 16,370 laboratory samples that were tested between April 4, 2014 and March 29, 2015. A total of 10,536 traceable individuals were identified, of whom 3,897 were confirmed cases (positive for Ebola virus RNA). There were significant differences in sex, age, and place of residence between confirmed and suspected cases that tested negative for Ebola virus RNA. Age (young children and the elderly) and place of residence (rural areas) were the risk factors for death due to the disease. The case fatality rate of confirmed cases decreased from 80% to 63% during the study period. These findings may help support future investigations and lead to a fuller understanding of the outbreak in Liberia.

Assessment and Optimization of the GeneXpert Diagnostic Platform for Detection of Ebola Virus RNA in Seminal Fluid

Recent studies have suggested that Ebola virus (EBOV) ribonucleic acid (RNA) potentially present in the semen of a large number of survivors of Ebola virus disease (EVD) in Western Africa may contribute to sexual transmission of EVD and generate new clusters of cases in regions previously declared EVD-free. These findings drive the immediate need for a reliable, rapid, user-friendly assay for detection of EBOV RNA in semen that is deployable to multiple sites across Western Africa. In this study, we optimized the Xpert EBOV assay for semen samples by adding dithiothreitol. Compared to the assays currently in use in Liberia (including Ebola Zaire Target 1, major groove binder real-time-polymerase chain reaction assays, and original Xpert EBOV assay), the modified Xpert EBOV assay demonstrated greater sensitivity than the comparator assays. Thus, the modified Xpert EBOV assay is optimal for large-scale monitoring of EBOV RNA persistence in male survivors.

Molecular analysis of the bacille Calmette-Guérin vaccine strain currently being used in Iran

BACKGROUND

In developing countries, tuberculosis (TB) infection control remains a challenge. The bacille Calmette-Guérin (BCG) vaccine is the only effective vaccine available for TB control. Iran uses a local BCG vaccine strain with an unknown substrain.

OBJECTIVE

To investigate the molecular characteristics of the current BCG strain being used in Iran using comparative genomics of the evolutionarily late strains, including BCG vaccines Pasteur, BCG-Danish, BCG-Glaxo, BCG-Prague, BCG-Frappier, BCG-Connaught and BCG-Moreau.

METHODS

A total of 67 different vials of BCG vaccine were cultured. DNA was extracted using the modified cetrimonium bromide (CTAB) method, and multiplex polymerase chain reaction (PCR) was performed to determine four target genomic regions of difference (RD) 1, RD8, RD16 and SenX3-RegX3, and to see whether RD2 and RD14 were present.

RESULTS

Our results showed that all studied batches were Mycobacterium bovis; molecular analysis revealed that the Iranian vaccine strains possess RD8, RD16 and SenX3-RegX3 regions but not RD1, RD2 and RD14. All of the vaccine batches analysed were compatible with BCG-Pasteur 1173p2, the original strain.

CONCLUSION

All of the BCG strains studied were recognised as the BCG-Pasteur 1173p2 strain. No genetic diversity among stocks and ready-for-use vaccine vials were detected.

The Opposite of Denial: Social Learning at the Onset of the Ebola Emergency in Liberia

This study analyzes findings from a rapid-response community-based qualitative research initiative to study the content of Ebola-related communications and the transmission of Ebola-related behaviors and practices through mass media communications and social learning in Monrovia, Liberia during August-September 2014. Thirteen neighborhoods in the common Monrovia media market were studied to appraise the reach of health communications and outreach regarding Ebola prevention and response measures. A World Health Organization (WHO) research team collected data on social learning and Ebola knowledge, attitudes, and practices through focus group-based discussions and key informant interviews over a 14-day period to assess the spread of information during a period of rapidly escalating crisis. Findings show that during a 2-week period, Monrovia neighborhood residents demonstrated rapid changes in beliefs about the source of Ebola, modes of contagion, and infection prevention and control (IPC) practices, discarding incorrect information. Changes in practices tended to lag behind the acquisition of learning. Findings also show that many continued to support conspiracy theories even as correct information was acquired. The implications for community engagement are substantial: (1) Under conditions of accelerating mortality, communities rapidly assimilate health information and abandon incorrect information; (2) Behavior change is likely to lag behind changes in beliefs due to local physical, structural, sociocultural, and institutional constraints; (3) Reports of "resistance" in Monrovia during the Ebola response were overstated and based on a limited number of incidents, and failed to account for specific local conditions and constraints.

Exposure Patterns Driving Ebola Transmission in West Africa: A Retrospective Observational Study

BACKGROUND

The ongoing West African Ebola epidemic began in December 2013 in Guinea, probably from a single zoonotic introduction. As a result of ineffective initial control efforts, an Ebola outbreak of unprecedented scale emerged. As of 4 May 2015, it had resulted in more than 19,000 probable and confirmed Ebola cases, mainly in Guinea (3,529), Liberia (5,343), and Sierra Leone (10,746). Here, we present analyses of data collected during the outbreak identifying drivers of transmission and highlighting areas where control could be improved.

METHODS AND FINDINGS

Over 19,000 confirmed and probable Ebola cases were reported in West Africa by 4 May 2015. Individuals with confirmed or probable Ebola ("cases") were asked if they had exposure to other potential Ebola cases ("potential source contacts") in a funeral or non-funeral context prior to becoming ill. We performed retrospective analyses of a case line-list, collated from national databases of case investigation forms that have been reported to WHO. These analyses were initially performed to assist WHO's response during the epidemic, and have been updated for publication. We analysed data from 3,529 cases in Guinea, 5,343 in Liberia, and 10,746 in Sierra Leone; exposures were reported by 33% of cases. The proportion of cases reporting a funeral exposure decreased over time. We found a positive correlation (r = 0.35, p < 0.001) between this proportion in a given district for a given month and the within-district transmission intensity, quantified by the estimated reproduction number (R). We also found a negative correlation (r = -0.37, p < 0.001) between R and the district proportion of hospitalised cases admitted within ≤4 days of symptom onset. These two proportions were not correlated, suggesting that reduced funeral attendance and faster hospitalisation independently influenced local transmission intensity. We were able to identify 14% of potential source contacts as cases in the case line-list. Linking cases to the contacts who potentially infected them provided information on the transmission network. This revealed a high degree of heterogeneity in inferred transmissions, with only 20% of cases accounting for at least 73% of new infections, a phenomenon often called super-spreading. Multivariable regression models allowed us to identify predictors of being named as a potential source contact. These were similar for funeral and non-funeral contacts: severe symptoms, death, non-hospitalisation, older age, and travelling prior to symptom onset. Non-funeral exposures were strongly peaked around the death of the contact. There was evidence that hospitalisation reduced but did not eliminate onward exposures. We found that Ebola treatment units were better than other health care facilities at preventing exposure from hospitalised and deceased individuals. The principal limitation of our analysis is limited data quality, with cases not being entered into the database, cases not reporting exposures, or data being entered incorrectly (especially dates, and possible misclassifications).

CONCLUSIONS

Achieving elimination of Ebola is challenging, partly because of super-spreading. Safe funeral practices and fast hospitalisation contributed to the containment of this Ebola epidemic. Continued real-time data capture, reporting, and analysis are vital to track transmission patterns, inform resource deployment, and thus hasten and maintain elimination of the virus from the human population.

Ebola and Its Control in Liberia, 2014-2015

Several factors explain the successful response to the outbreak in this country.

The severe epidemic of Ebola virus disease in Liberia started in March 2014. On May 9, 2015, the World Health Organization declared Liberia free of Ebola, 42 days after safe burial of the last known case-patient. However, another 6 cases occurred during June–July; on September 3, 2015, the country was again declared free of Ebola. Liberia had by then reported 10,672 cases of Ebola and 4,808 deaths, 37.0% and 42.6%, respectively, of the 28,103 cases and 11,290 deaths reported from the 3 countries that were heavily affected at that time. Essential components of the response included government leadership and sense of urgency, coordinated international assistance, sound technical work, flexibility guided by epidemiologic data, transparency and effective communication, and efforts by communities themselves. Priorities after the epidemic include surveillance in case of resurgence, restoration of health services, infection control in healthcare settings, and strengthening of basic public health systems.

Community-based reports of morbidity, mortality, and health-seeking behaviours in four Monrovia communities during the West African Ebola epidemic

The goal of this study was to assess morbidity, mortality, and health-seeking behaviours during the 2014 Ebola outbreak in Monrovia, Liberia. This study examined commonly reported symptoms of illness, pre-clinical diagnostic practices, typical healthcare-seeking strategies, and health resources available to populations, in order to identify salient needs and gaps in healthcare that would inform local emergency response efforts. Semi-structured interviews were conducted with household members in four Monrovia neighbourhoods. Researchers used a multi-stage cluster approach to recruit participants. Within 555 households sampled, 505 individuals were reported sick (69%) or recently sick (38%) or deceased (7%). Common self-diagnoses included malaria, hypertension, influenza, typhoid, and Ebola. The most cited health-seeking strategy was to purchase medications from the private sector. Respondents also obtained healthcare from community members known to have medical experience. Findings suggest that non-formal healthcare systems played an important role in managing morbidity during the West African Ebola virus disease (EVD) outbreak. Lay community members engaged in complex assessments of health symptoms and sought biomedical care at rates perhaps higher than anticipated during the response. This study highlights how informal networks of healthcare providers can play an important role in preventing and curbing future emerging disease outbreaks.

Reduced evolutionary rate in reemerged Ebola virus transmission chains

On 29 June 2015, Liberia's respite from Ebola virus disease (EVD) was interrupted for the second time by a renewed outbreak ("flare-up") of seven confirmed cases. We demonstrate that, similar to the March 2015 flare-up associated with sexual transmission, this new flare-up was a reemergence of a Liberian transmission chain originating from a persistently infected source rather than a reintroduction from a reservoir or a neighboring country with active transmission. Although distinct, Ebola virus (EBOV) genomes from both flare-ups exhibit significantly low genetic divergence, indicating a reduced rate of EBOV evolution during persistent infection. Using this rate of change as a signature, we identified two additional EVD clusters that possibly arose from persistently infected sources. These findings highlight the risk of EVD flare-ups even after an outbreak is declared over.

Retrospective Analysis of the 2014-2015 Ebola Epidemic in Liberia

The 2014-2015 Ebola epidemic has been the most protracted and devastating in the history of the disease. To prevent future outbreaks on this scale, it is imperative to understand the reasons that led to eventual disease control. Here, we evaluated the shifts of Ebola dynamics at national and local scales during the epidemic in Liberia. We used a transmission model calibrated to epidemiological data between June 9 and December 31, 2014, to estimate the extent of community and hospital transmission. We found that despite varied local epidemic patterns, community transmission was reduced by 40-80% in all the counties analyzed. Our model suggests that the tapering of the epidemic was achieved through reductions in community transmission, rather than accumulation of immune individuals through asymptomatic infection and unreported cases. Although the times at which this transmission reduction occurred in the majority of the Liberian counties started before any large expansion in hospital capacity and the distribution of home protection kits, it remains difficult to associate the presence of interventions with reductions in Ebola incidence.

Elimination of Ebola Virus Transmission in Liberia - September 3, 2015

Following 42 days since the last Ebola virus disease (Ebola) patient was discharged from a Liberian Ebola treatment unit (ETU), September 3, 2015, marks the second time in a 4-month period that the World Health Organization (WHO) has declared Liberia free of Ebola virus transmission (1). The first confirmed Ebola cases in West Africa were identified in southeastern Guinea on March 23, 2014, and within 1 week, cases were identified and confirmed in Liberia (1). Since then, Liberia has reported 5,036 confirmed and probable Ebola cases and 4,808 Ebola-related deaths. The epidemic in Liberia peaked in late summer and early fall of 2014, when more than 200 confirmed and probable cases were reported each week .

Risk assessment of gas oil and kerosene contamination on some properties of silty clay soil

Soil and ground water resource pollution by petroleum compounds and chemical solvents has multiple negative environmental impacts. The aim of this research was to investigate the impacts of kerosene and gas oil pollutants on some physical and chemical properties, breakthrough curve (BTC), and water retention curve (SWRC) of silty clay soil during a 3-month period. Therefore, some water-saturated soils were artificially contaminated in the pulse condition inside some glassy cylinders by applying half and one pore volume of these pollutants, and then parametric investigations of the SWRC were performed using RETC software for Van Genukhten and Brooks-Corey equations in the various suctions and the soil properties were determined before and after pollution during 3 months. The results showed that gas oil and kerosene had a slight effect on soil pH and caused the cumulative enhancement in the soil respiration, increase in the bulk density and organic matter, and reduction in the soil porosity and electrical and saturated hydraulic conductivity. Furthermore, gas oil retention was significantly more than kerosene (almost 40%) in the soil. The survey of SWRC indicated that the contaminated soil samples had a little higher amount of moisture retention (just under 15% in most cases) compared to the unpolluted ones during this 3-month period. The parametric analysis of SWRC demonstrated an increase in the saturated water content, Θ s, from nearly 49% in the control sample to just under 53% in the polluted ones. Contaminants not only decreased the residual water content, Θ r, but also reduced the SWRC gradient, n, and amount of α parameter. The evaluation of both equations revealed more accurate prediction of SWRC's parameters by Van Genukhten compared to those of Brooks and Corey.

The risk of contralateral breast cancer in daughters of women with and without breast cancer

We aimed to estimate the 15-year and lifetime risks of contralateral breast cancer in breast cancer patients according to the age of diagnosis of the first cancer and the history of breast cancer in the mother. The risks of contralateral breast cancer were estimated for all 78,775 breast cancer patients in the Swedish Family-Cancer Database (age at diagnosis of first breast cancer <70 years). The risk of experiencing a contralateral breast cancer within 15 years of diagnosis was 8.4% [95% confidence interval (CI): 8.1-8.7%] for women with an unaffected mother, was 12% (95%CI: 11-13%) for a woman with a mother with unilateral breast cancer and was 13% (95%CI: 9.5-17%) for women with a mother with bilateral breast cancer. In early-onset diagnosed women (<50 years) with an unaffected mother, the risk of contralateral breast cancer until age 80 was 23% (95%CI: 20-26%) and for late-onset (50-69 years) diagnosed women it was 17% (95%CI: 14-21%). In a woman with a mother with an early-onset unilateral breast cancer, risk of contralateral breast cancer by age 80 was 35% (95%CI: 25-46%). Women with a mother with early-onset bilateral breast cancer had 31% (95%CI: 12-67%) lifetime risk of contralateral breast cancer. The risk of contralateral breast cancer is higher for daughters of breast cancer patients than for daughters of women without breast cancer. Maternal cancer history and age at onset of first breast cancer in women should be taken into account when counseling breast cancer patients about their risk of contralateral breast cancer.

Controlling the last known cluster of Ebola virus disease - Liberia, January-February 2015

As one of the three West African countries highly affected by the 2014-2015 Ebola virus disease (Ebola) epidemic, Liberia reported approximately 10,000 cases. The Ebola epidemic in Liberia was marked by intense urban transmission, multiple community outbreaks with source cases occurring in patients coming from the urban areas, and outbreaks in health care facilities (HCFs). This report, based on data from routine case investigations and contact tracing, describes efforts to stop the last known chain of Ebola transmission in Liberia. The index patient became ill on December 29, 2014, and the last of 21 associated cases was in a patient admitted into an Ebola treatment unit (ETU) on February 18, 2015. The chain of transmission was stopped because of early detection of new cases; identification, monitoring, and support of contacts in acceptable settings; effective triage within the health care system; and rapid isolation of symptomatic contacts. In addition, a "sector" approach, which divided Montserrado County into geographic units, facilitated the ability of response teams to rapidly respond to community needs. In the final stages of the outbreak, intensive coordination among partners and engagement of community leaders were needed to stop transmission in densely populated Montserrado County. A companion report describes the efforts to enhance infection prevention and control efforts in HCFs. After February 19, no additional clusters of Ebola cases have been detected in Liberia. On May 9, the World Health Organization declared the end of the Ebola outbreak in Liberia.

Initiation of a ring approach to infection prevention and control at non-Ebola health care facilities - Liberia, January-February 2015

From mid-January to mid-February 2015, all confirmed Ebola virus disease (Ebola) cases that occurred in Liberia were epidemiologically linked to a single index patient from the St. Paul Bridge area of Montserrado County. Of the 22 confirmed patients in this cluster, eight (36%) sought and received care from at least one of 10 non-Ebola health care facilities (HCFs), including clinics and hospitals in Montserrado and Margibi counties, before admission to an Ebola treatment unit. After recognition that three patients in this emerging cluster had received care from a non-Ebola treatment unit, and in response to the risk for Ebola transmission in non-Ebola treatment unit health care settings, a focused infection prevention and control (IPC) rapid response effort for the immediate area was developed to target facilities at increased risk for exposure to a person with Ebola (Ring IPC). The Ring IPC approach, which provided rapid, intensive, and short-term IPC support to HCFs in areas of active Ebola transmission, was an addition to Liberia's proposed longer term national IPC strategy, which focused on providing a comprehensive package of IPC training and support to all HCFs in the country. This report describes possible health care worker exposures to the cluster's eight patients who sought care from an HCF and implementation of the Ring IPC approach. On May 9, 2015, the World Health Organization (WHO) declared the end of the Ebola outbreak in Liberia.

Harnessing case isolation and ring vaccination to control Ebola

As a devastating Ebola outbreak in West Africa continues, non-pharmaceutical control measures including contact tracing, quarantine, and case isolation are being implemented. In addition, public health agencies are scaling up efforts to test and deploy candidate vaccines. Given the experimental nature and limited initial supplies of vaccines, a mass vaccination campaign might not be feasible. However, ring vaccination of likely case contacts could provide an effective alternative in distributing the vaccine. To evaluate ring vaccination as a strategy for eliminating Ebola, we developed a pair approximation model of Ebola transmission, parameterized by confirmed incidence data from June 2014 to January 2015 in Liberia and Sierra Leone. Our results suggest that if a combined intervention of case isolation and ring vaccination had been initiated in the early fall of 2014, up to an additional 126 cases in Liberia and 560 cases in Sierra Leone could have been averted beyond case isolation alone. The marginal benefit of ring vaccination is predicted to be greatest in settings where there are more contacts per individual, greater clustering among individuals, when contact tracing has low efficacy or vaccination confers post-exposure protection. In such settings, ring vaccination can avert up to an additional 8% of Ebola cases. Accordingly, ring vaccination is predicted to offer a moderately beneficial supplement to ongoing non-pharmaceutical Ebola control efforts.

Community-centered responses to Ebola in urban Liberia: the view from below

BACKGROUND

The West African Ebola epidemic has demonstrated that the existing range of medical and epidemiological responses to emerging disease outbreaks is insufficient, especially in post-conflict contexts with exceedingly poor healthcare infrastructures. In this context, community-based responses have proven vital for containing Ebola virus disease (EVD) and shifting the epidemic curve. Despite a surge in interest in local innovations that effectively contained the epidemic, the mechanisms for community-based response remain unclear. This study provides baseline information on community-based epidemic control priorities and identifies innovative local strategies for containing EVD in Liberia.

METHODOLOGY/PRINCIPAL FINDINGS

This study was conducted in September 2014 in 15 communities in Monrovia and Montserrado County, Liberia--one of the epicenters of the Ebola outbreak. Findings from 15 focus group discussions with 386 community leaders identified strategies being undertaken and recommendations for what a community-based response to Ebola should look like under then-existing conditions. Data were collected on the following topics: prevention, surveillance, care-giving, community-based treatment and support, networks and hotlines, response teams, Ebola treatment units (ETUs) and hospitals, the management of corpses, quarantine and isolation, orphans, memorialization, and the need for community-based training and education. Findings have been presented as community-based strategies and recommendations for (1) prevention, (2) treatment and response, and (3) community sequelae and recovery. Several models for community-based management of the current Ebola outbreak were proposed. Additional findings indicate positive attitudes towards early Ebola survivors, and the need for community-based psychosocial support.

CONCLUSIONS/SIGNIFICANCE

Local communities' strategies and recommendations give insight into how urban Liberian communities contained the EVD outbreak while navigating the systemic failures of the initial state and international response. Communities in urban Liberia adapted to the epidemic using multiple coping strategies. In the absence of health, infrastructural and material supports, local people engaged in self-reliance in order to contain the epidemic at the micro-social level. These innovations were regarded as necessary, but as less desirable than a well-supported health-systems based response; and were seen as involving considerable individual, social, and public health costs, including heightened vulnerability to infection.