title: Successful Control of Ebola Virus Disease: Analysis of Service Based Data from Rural Sierra Leone.
abstract: BACKGROUND
  The scale and geographical distribution of the current outbreak in West Africa raised doubts as to the effectiveness of established methods of control. Ebola Virus Disease (EVD) was first detected in Sierra Leone in May 2014 in Kailahun district. Despite high case numbers elsewhere in the country, transmission was eliminated in the district by December 2014. We describe interventions underpinning successful EVD control in Kailahun and implications for EVD control in other areas.
  
  
  METHODS
  Internal service data and published reports from response agencies were analysed to describe the structure and type of response activities, EVD case numbers and epidemic characteristics. This included daily national situation reports and District-level data and reports of the Sierra Leone Ministry of Health and Sanitation, and Médecins Sans Frontières (MSF) patient data and internal epidemiological reports. We used EVD case definitions provided by the World Health Organisation over the course of the outbreak. Characteristics assessed included level of response activities and epidemiological features such as reported exposure (funeral-related or not), time interval between onset of illness and admission to the EVD Management Centre (EMC), work-related exposures (health worker or not) and mortality. We compared these characteristics between two time periods--June to July (the early period of response), and August to December (when coverage and quality of response had improved). A stochastic model was used to predict case numbers per generation with different numbers of beds and a varying percentage of community cases detected.
  
  
  RESULTS
  There were 652 probable/confirmed EVD cases from June-December 2014 in Kailahun. An EMC providing patient care opened in June. By August 2014 an integrated detection, treatment, and prevention strategy was in place across the district catchment zone. From June-July to August-December 2014 surveillance and contact tracing staff increased from 1.0 to 8.8 per confirmed EVD case, EMC capacity increased from 32 to 100 beds, the number of burial teams doubled, and health promotion activities increased in coverage. These improvements in response were associated with the following changes between the same periods: the proportion of confirmed/probable cases admitted to the EMC increased from 35% to 83% (χ(2) p-value<0·001), the proportion of confirmed patients admitted to the EMC <3 days of symptom onset increased from 19% to 37% (χ(2) p-value <0·001), and reported funeral contact in those admitted decreased from 33% to 16% (χ(2) p-value <0·001). Mathematical modelling confirmed the importance of both patient management capacity and surveillance and contact tracing for EVD control.
  
  
  CONCLUSIONS
  Our findings demonstrate that control of EVD can be achieved using established interventions based on identification and appropriate management of those who are at risk of and develop EVD, including in the context of ongoing transmission in surrounding regions. Key attributes in achieving control were sufficient patient care capacity (including admission to specialist facilities of suspect and probable cases for assessment), integrated with adequate staffing and resourcing of community-based case detection and prevention activities. The response structure and coverage targets we present are of value in informing effective control in current and future EVD outbreaks.
authors.affiliation: Manson Unit, Médecins Sans Frontières, London, United Kingdom.|National Centre for Epidemiology and Population Health, Research School of Population Health, Australian National University, Canberra, Australia.
authors.forename: Kamalini
authors.initials: K
authors.lastname: Lokuge
authors.affiliation: Manson Unit, Médecins Sans Frontières, London, United Kingdom.
authors.forename: Grazia
authors.initials: G
authors.lastname: Caleo
authors.affiliation: Manson Unit, Médecins Sans Frontières, London, United Kingdom.
authors.forename: Jane
authors.initials: J
authors.lastname: Greig
authors.affiliation: Médecins Sans Frontières, Kailahun, Sierra Leone.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Duncombe
authors.affiliation: Médecins Sans Frontières, Kailahun, Sierra Leone.
authors.forename: Nicholas
authors.initials: N
authors.lastname: McWilliam
authors.affiliation: District Health Management Team, Ministry of Health and Sanitation, Kailahun, Sierra Leone.
authors.forename: James
authors.initials: J
authors.lastname: Squire
authors.affiliation: District Health Management Team, Ministry of Health and Sanitation, Kailahun, Sierra Leone.
authors.forename: Manjo
authors.initials: M
authors.lastname: Lamin
authors.affiliation: Médecins Sans Frontières, Kailahun, Sierra Leone.
authors.forename: Emily
authors.initials: E
authors.lastname: Veltus
authors.affiliation: Operational Centre Geneva, Médecins Sans Frontières, Geneva, Switzerland.
authors.forename: Anja
authors.initials: A
authors.lastname: Wolz
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, University of Manitoba, Winnipeg, Canada.
authors.forename: Gary
authors.initials: G
authors.lastname: Kobinger
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, University of Manitoba, Winnipeg, Canada.
authors.forename: Marc-Antoine
authors.initials: MA
authors.lastname: de la Vega
authors.affiliation: District Health Management Team, Ministry of Health and Sanitation, Kailahun, Sierra Leone.
authors.forename: Osman
authors.initials: O
authors.lastname: Gbabai
authors.affiliation: District Health Management Team, Ministry of Health and Sanitation, Kailahun, Sierra Leone.
authors.forename: Sao
authors.initials: S
authors.lastname: Nabieu
authors.affiliation: District Health Management Team, Ministry of Health and Sanitation, Kailahun, Sierra Leone.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Lamin
authors.affiliation: Operational Centre Amsterdam, Médecins Sans Frontières, Amsterdam, The Netherlands.
authors.forename: Ronald
authors.initials: R
authors.lastname: Kremer
authors.affiliation: Médecins Sans Frontières, Kailahun, Sierra Leone.|European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control, (ECDC), Stockholm, Sweden.|Institut de Veille Sanitaire, Paris, France.
authors.forename: Kostas
authors.initials: K
authors.lastname: Danis
authors.affiliation: National Centre for Epidemiology and Population Health, Research School of Population Health, Australian National University, Canberra, Australia.
authors.forename: Emily
authors.initials: E
authors.lastname: Banks
authors.affiliation: National Centre for Epidemiology and Population Health, Research School of Population Health, Australian National University, Canberra, Australia.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Glass
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003140:Communicable Disease Control / Q000379:methods*; D005260:Female; D006268:Health Facilities; D058016:Health Facility Administration; D006297:Health Services Accessibility; D006302:Health Services Research; D019142:Hemorrhagic Fever, Ebola / Q000453:epidemiology* / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012424:Rural Population; D012807:Sierra Leone / Q000453:epidemiology; D000078329:Workforce; D055815:Young Adult