title: Evaluation of a point-of-care blood test for identification of Ebola virus disease at Ebola holding units, Western Area, Sierra Leone, January to February 2015.
abstract: Current Ebola virus disease (EVD) diagnosis relies on reverse transcription-PCR (RT-PCR) technology, requiring skilled laboratory personnel and technical infrastructure. Lack of laboratory diagnostic capacity has led to diagnostic delays in the current West African EVD outbreak of 2014 and 2015, compromising outbreak control. We evaluated the diagnostic accuracy of the EVD bedside rapid diagnostic antigen test (RDT) developed by the United Kingdom's Defence Science and Technology Laboratory, compared with Ebola virus RT-PCR, in an operational setting for EVD diagnosis of suspected cases admitted to Ebola holding units in the Western Area of Sierra Leone. From 22 January to 16 February 2015, 138 participants were enrolled. EVD prevalence was 11.5%. All EVD cases were identified by a positive RDT with a test line score of 6 or more, giving a sensitivity of 100% (95% confidence interval (CI): 78.2-100). The corresponding specificity was high (96.6%, 95% CI: 91.3-99.1). The positive and negative predictive values for the population prevalence were 79.0% (95% CI: 54.4-93.8) and 100% (95% CI: 96.7-100), respectively. These results, if confirmed in a larger study, suggest that this RDT could be used as a 'rule-out' screening test for EVD to improve rapid case identification and resource allocation.
authors.affiliation: King s Sierra Leone Partnership, King's Centre for Global Health, King's College London, and King s Health Partners, London, United Kingdom.
authors.forename: N F
authors.initials: NF
authors.lastname: Walker
authors.forename: C S
authors.initials: CS
authors.lastname: Brown
authors.forename: D
authors.initials: D
authors.lastname: Youkee
authors.forename: P
authors.initials: P
authors.lastname: Baker
authors.forename: N
authors.initials: N
authors.lastname: Williams
authors.forename: A
authors.initials: A
authors.lastname: Kalawa
authors.forename: K
authors.initials: K
authors.lastname: Russell
authors.forename: A F
authors.initials: AF
authors.lastname: Samba
authors.forename: N
authors.initials: N
authors.lastname: Bentley
authors.forename: F
authors.initials: F
authors.lastname: Koroma
authors.forename: M B
authors.initials: MB
authors.lastname: King
authors.forename: B E
authors.initials: BE
authors.lastname: Parker
authors.forename: M
authors.initials: M
authors.lastname: Thompson
authors.forename: T
authors.initials: T
authors.lastname: Boyles
authors.forename: B
authors.initials: B
authors.lastname: Healey
authors.forename: B
authors.initials: B
authors.lastname: Kargbo
authors.forename: D
authors.initials: D
authors.lastname: Bash-Taqi
authors.forename: A J
authors.initials: AJ
authors.lastname: Simpson
authors.forename: A
authors.initials: A
authors.lastname: Kamara
authors.forename: T B
authors.initials: TB
authors.lastname: Kamara
authors.forename: M
authors.initials: M
authors.lastname: Lado
authors.forename: O
authors.initials: O
authors.lastname: Johnson
authors.forename: T
authors.initials: T
authors.lastname: Brooks
mesh_terms: D004196:Disease Outbreaks / Q000517:prevention & control*; D029043:Ebolavirus / Q000235:genetics / Q000302:isolation & purification*; D058872:Epidemics; D005260:Female; D006403:Hematologic Tests / Q000379:methods*; D019142:Hemorrhagic Fever, Ebola / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D006801:Humans; D008297:Male; D019095:Point-of-Care Systems; D011237:Predictive Value of Tests; D015995:Prevalence; D012367:RNA, Viral / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D012807:Sierra Leone / Q000453:epidemiology; D013997:Time Factors
chemical_list: D012367:RNA, Viral