title: Factors Underlying Ebola Virus Infection Among Health Workers, Kenema, Sierra Leone, 2014-2015.
abstract: Ebola virus disease (EVD) in health workers (HWs) has been a major challenge during the 2014-2015 outbreak. We examined factors associated with Ebola virus exposure and mortality in HWs in Kenema District, Sierra Leone.
  
  
  
  We analyzed data from the Sierra Leone National Viral Hemorrhagic Fever Database, contact tracing records, Kenema Government Hospital (KGH) staff and Ebola Treatment Unit (ETU) rosters, and burial logs.
  
  
  
  From May 2014 through January 2015, 600 cases of EVD originated in Kenema District, including 92 (15%) HWs, 66 (72%) of whom worked at KGH. Among KGH medical staff and international volunteers, 18 of 62 (29%) who worked in the ETU developed EVD, compared with 48 of 83 (58%) who worked elsewhere in the hospital. Thirteen percent of HWs with EVD reported contact with EVD patients, while 27% reported contact with other infected HWs. The number of HW EVD cases at KGH declined roughly 1 month after implementation of a new triage system at KGH and the opening of a second ETU within the district. The case fatality ratio for HWs and non-HWs with EVD was 69% and 74%, respectively.
  
  
  
  The cluster of HW EVD cases in Kenema District is one of the largest ever reported. Most HWs with EVD had potential virus exposure both inside and outside of hospitals. Prevention measures for HWs must address a spectrum of infection risks in both formal and informal care settings as well as in the community.
authors.affiliation: Department of Pandemic and Epidemic Diseases, World Health Organization, Geneva, Switzerland.
authors.forename: Mikiko
authors.initials: M
authors.lastname: Senga
authors.affiliation: Epidemic Intelligence Service, US Centers for Disease Prevention and Control, Atlanta, Georgia.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Pringle
authors.affiliation: Special Programme for Research and Training in Tropical Diseases, World Health Organization, Geneva, Switzerland University of St Andrews Medical School, Fife, Scotland.
authors.forename: Andrew
authors.initials: A
authors.lastname: Ramsay
authors.affiliation: Infectious Diseases Directorate, Naval Medical Research Center, Silver Spring, Maryland.
authors.forename: David M
authors.initials: DM
authors.lastname: Brett-Major
authors.affiliation: Department of Medicine and Interdepartmental Division of Critical Care Medicine, University of Toronto, Ontario, Canada.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Fowler
authors.affiliation: Kenema Government Hospital, Kenema District, Sierra Leone.
authors.forename: Issa
authors.initials: I
authors.lastname: French
authors.affiliation: Kenema Government Hospital, Kenema District, Sierra Leone.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Vandi
authors.affiliation: Kenema Government Hospital, Kenema District, Sierra Leone.
authors.forename: Josephine
authors.initials: J
authors.lastname: Sellu
authors.affiliation: Kenema Government Hospital, Kenema District, Sierra Leone.
authors.forename: Christian
authors.initials: C
authors.lastname: Pratt
authors.affiliation: Kenema Government Hospital, Kenema District, Sierra Leone.
authors.forename: Josephine
authors.initials: J
authors.lastname: Saidu
authors.affiliation: Department of Pandemic and Epidemic Diseases, World Health Organization, Geneva, Switzerland.
authors.forename: Nahoko
authors.initials: N
authors.lastname: Shindo
authors.affiliation: Department of Pandemic and Epidemic Diseases, World Health Organization, Geneva, Switzerland.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Bausch
mesh_terms: D000328:Adult; D004196:Disease Outbreaks; D029043:Ebolavirus / Q000502:physiology*; D005260:Female; D006282:Health Personnel; D019142:Hemorrhagic Fever, Ebola / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D006761:Hospitals; D006801:Humans; D008297:Male; D008875:Middle Aged; D012807:Sierra Leone / Q000453:epidemiology
keywords: Ebola; health worker; infection prevention and control; outbreak; viral hemorrhagic fever