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Concept: Northern Province, Sierra Leone


Kambia District is located in northwestern Sierra Leone along the international border with Guinea. The district is dominated by forest and swamp habitat and has a population of approximately 270,000 persons (approximately 5% of the nation’s population) who live in rural villages and predominantly subsist on farming and trading. During 2014-2015, the remoteness of the area, a highly porous border with Guinea, and strong traditional beliefs about health care and sickness led to unique challenges in controlling the Ebola Virus Disease (Ebola) outbreak within the district.

Concepts: Sierra Leone, Temne people, Northern Province, Sierra Leone, Port Loko District, Districts of Sierra Leone, Bombali District, Kambia District, Susu people


This paper discusses the establishment of a clinical trial of an Ebola vaccine candidate in Kambia District, Northern Sierra Leone during the epidemic, and analyses the role of social science research in ensuring that lessons from the socio-political context, the recent experience of the Ebola outbreak, and learning from previous clinical trials were incorporated in the development of community engagement strategies. The paper aims to provide a case study of an integrated social science and communications system in the start-up phase of the clinical trial.

Concepts: Sierra Leone, Temne people, Northern Province, Sierra Leone, Port Loko District, Districts of Sierra Leone, Bombali District, Kambia District, Susu people


During the 2014-16 Ebola virus disease (EVD) outbreak, the Magburaka Ebola Management Centre (EMC) operated by Médecins Sans Frontières (MSF) in Tonkolili District, Sierra Leone, identified that available district maps lacked up-to-date village information to facilitate timely implementation of EVD control strategies. In January 2015, we undertook a survey in chiefdoms within the MSF EMC catchment area to collect mapping and village data. We explore the feasibility and cost to mobilise a local community for this survey, describe validation against existing mapping sources and use of the data to prioritise areas for interventions, and lessons learned.

Concepts: Sierra Leone, Temne people, Northern Province, Sierra Leone, Tonkolili District, Foday Sankoh, Districts of Sierra Leone, Reston, Virginia, Magburaka


The Ebola virus disease (EVD) epidemic that hit West Africa in 2013 was the worst outbreak of EVD in recorded history. While much has been published regarding the international and national-level EVD responses, there is a dearth of literature on district-level coordination and operational structures, successes, and failures. This article seeks to understand how the EVD response unfolded at the district level, namely the challenges to operationalizing EVD surveillance over the course of the outbreak in Port Loko and Kambia districts of Sierra Leone. We present here GOAL Global’s understanding of the fundamental challenges to case investigation operations during the EVD response, including environmental and infrastructural, sociocultural, and political and organizational challenges, with insight complemented by a survey of 42 case investigators. Major challenges included deficiencies in transportation and communication resources, low morale and fatigue among case investigators, mismanagement of data, mistrust among communities, and leadership challenges. Without addressing these operational challenges, technical surveillance solutions are difficult to implement and hold limited relevance, due to the poor quality and quantity of data being collected. The low prioritization of operational needs came at a high cost. To mediate this, GOAL addressed these operational challenges by acquiring critical transportation and communication resources to facilitate case investigation, including vehicles, boats, fuel, drivers, phones, and closed user groups; addressing fatigue and low morale by hiring more case investigators, making timely payments, arranging for time off, and providing meals and personal protective equipment; improving data tracking efforts through standard operating procedures, training, and mentorship to build higher-quality case histories and make it easier to access information; strengthening trust in communities by ensuring familiarity and consistency of case investigators; and improving operational leadership challenges through meetings and regular coordination, establishing an active surveillance strategy in Port Loko, and conducting an after-action review. Resolving or addressing these challenges was of primary importance, and requisite for the implementation of technical epidemiological complements to EVD case investigation.

Concepts: Ebola, Malaise, Sierra Leone, Temne people, Port Loko, Northern Province, Sierra Leone, Sorie Ibrahim Koroma, Port Loko District


Case-fatality rates in Ebola treatment centers (ETCs) varied widely during the Ebola virus disease (EVD) outbreak in West Africa. We assessed the influence of referral pathway on ETC case-fatality rates with a retrospective cohort of 126 patients treated at the Mathaska ETC in Port Loko, Sierra Leone. The patients consisted of persons who had confirmed EVD when transferred to the ETC or who had been diagnosed onsite. The case-fatality rate for transferred patients was 46% versus 67% for patients diagnosed onsite (p = 0.02). The difference was mediated by Ebola viral load at diagnosis, suggesting a survival selection bias. Comparisons of case-fatality rates across ETCs and clinical management strategies should account for potential survival selection bias.

Concepts: Microbiology, Viral hemorrhagic fever, Liberia, Sierra Leone, Temne people, Port Loko, Northern Province, Sierra Leone, Sorie Ibrahim Koroma


On January 14, 2016, the Sierra Leone Ministry of Health and Sanitation was notified that a buccal swab collected on January 12 from a deceased female aged 22 years (patient A) in Tonkolili District had tested positive for Ebola virus by reverse transcription-polymerase chain reaction (RT-PCR). The most recent case of Ebola virus disease (Ebola) in Sierra Leone had been reported 4 months earlier on September 13, 2015 (1), and the World Health Organization had declared the end of Ebola virus transmission in Sierra Leone on November 7, 2015 (2). The Government of Sierra Leone launched a response to prevent further transmission of Ebola virus by identifying contacts of the decedent and monitoring them for Ebola signs and symptoms, ensuring timely treatment for anyone with Ebola, and conducting an epidemiologic investigation to identify the source of infection.

Concepts: Epidemiology, Disease, Death, Sierra Leone, Northern Province, Sierra Leone, Tonkolili District, Foday Sankoh, Magburaka


Understanding the growth and spatial expansion of (re)emerging infectious disease outbreaks, such as Ebola and avian influenza, is critical for the effective planning of control measures; however, such efforts are often compromised by data insufficiencies and observational errors. Here, we develop a spatial-temporal inference methodology using a modified network model in conjunction with the ensemble adjustment Kalman filter, a Bayesian inference method equipped to handle observational errors. The combined method is capable of revealing the spatial-temporal progression of infectious disease, while requiring only limited, readily compiled data. We use this method to reconstruct the transmission network of the 2014-2015 Ebola epidemic in Sierra Leone and identify source and sink regions. Our inference suggests that, in Sierra Leone, transmission within the network introduced Ebola to neighbouring districts and initiated self-sustaining local epidemics; two of the more populous and connected districts, Kenema and Port Loko, facilitated two independent transmission pathways. Epidemic intensity differed by district, was highly correlated with population size (r = 0.76, p = 0.0015) and a critical window of opportunity for containing local Ebola epidemics at the source (ca one month) existed. This novel methodology can be used to help identify and contain the spatial expansion of future (re)emerging infectious disease outbreaks.

Concepts: Epidemiology, Infectious disease, Influenza, Pandemic, Sierra Leone, Temne people, Port Loko, Northern Province, Sierra Leone


Mortality surveillance and vital registration are limited in Sierra Leone, a country with one of the highest mortality rates among children aged <5 years worldwide, approximately 120 deaths per 1,000 live births (1,2). To inform efforts to strengthen surveillance, stillbirths and deaths in children aged <5 years from multiple surveillance streams in Bombali Sebora chiefdom were retrospectively reviewed. In total, during January 2015-November 2016, 930 deaths in children aged <5 years were identified, representing 73.3% of the 1,269 deaths that were expected based on modeled estimates. The "117" telephone alert system established during the Ebola virus disease (Ebola) epidemic captured 683 (73.4%) of all reported deaths in children aged <5 years, and was the predominant reporting source for stillbirths (n = 172). In the absence of complete vital events registration, 117 call alerts markedly improved the completeness of reporting of stillbirths and deaths in children aged <5 years.

Concepts: Death, Sierra Leone, Ernest Bai Koroma, Temne people, Northern Province, Sierra Leone, Bombali District, Makeni, Joseph Saidu Momoh


As part of the UK response to the 2013-2016 Ebola virus disease (EVD) epidemic in West Africa, Public Health England (PHE) were tasked with establishing three field Ebola virus (EBOV) diagnostic laboratories in Sierra Leone by the UK Department for International Development (DFID). These provided diagnostic support to the Ebola Treatment Centre (ETC) facilities located in Kerry Town, Makeni and Port Loko. The Novel and Dangerous Pathogens (NADP) Training group at PHE, Porton Down, designed and implemented a pre-deployment Ebola diagnostic laboratory training programme for UK volunteer scientists being deployed to the PHE EVD laboratories. Here, we describe the training, workflow and capabilities of these field laboratories for use in response to disease epidemics and in epidemiological surveillance. We discuss the training outcomes, the laboratory outputs, lessons learned and the legacy value of the support provided. We hope this information will assist in the recruitment and training of staff for future responses and in the design and implementation of rapid deployment diagnostic field laboratories for future outbreaks of high consequence pathogens.This article is part of the themed issue ‘The 2013-2016 West African Ebola epidemic: data, decision-making and disease control’.

Concepts: Epidemiology, Nigeria, West Africa, Liberia, Atlantic slave trade, Sierra Leone, Port Loko, Northern Province, Sierra Leone


In 2010, at the same time as the national roll out of the Free Health Care Initiative (FHCI), which removed user fees for facility based health care, trained community health volunteers (CHVs) were deployed to provide integrated community case management of diarrhea, malaria and pneumonia to children under 5 years of age (U5) in Kambia and Pujehun districts, Sierra Leone. After 2 years of implementation and in the context of FHCI, CHV utilization rate was 14.0 %. In this study, we examine the factors associated with this level of CHV utilization. A cross-sectional household-cluster survey of 1590 caregivers of 2279 children U5 was conducted in 2012; with CHV utilization assessed using a multiple logistic regression model. Focus groups and in-depth interviews were also conducted to understand communities' experiences with CHVs. Children with diarrhea (OR = 3.17, 95 % CI: 1.17-8.60), from female-headed households (OR = 4.55, 95 % CI: 1.88-11.00), and whose caregivers reported poor quality of care as a barrier to facility care-seeking (OR = 8.53, 95 % CI: 3.13-23.16) were more likely to receive treatment from a CHV. Despite low utilization, caregivers were highly familiar and appreciative of CHVs, but were concerned about the lack of financial remuneration for CHVs. CHVs remained an important source of care for children from female-headed households and whose caregivers reported poor quality of care at health facilities. CHVs are an important strategy for certain populations even when facility utilization is high or when facility services are compromised, as has happened with the recent Ebola epidemic in Sierra Leone.

Concepts: Health care, Regression analysis, Logistic regression, Sierra Leone, Northern Province, Sierra Leone, Districts of Sierra Leone, Southern Province, Sierra Leone, Kambia District