Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Analytical Performance Characteristics of the Cepheid GeneXpert Ebola Assay for the Detection of Ebola Virus

Journal Article · · PLoS ONE
 [1];  [2];  [3];  [4];  [5];  [4];  [4];  [5];  [5];  [5];  [5];  [5];  [5];  [6];  [6];  [6];  [7];  [8];  [9];  [10] more »;  [5] « less
  1. Stanford Univ. School of Medicine, CA (United States). Dept. of Pathology; Stanford Univ. School of Medicine, CA (United States). Dept. of Medicine, Division of Infectious Diseases and Geographic Medicine
  2. Stanford Univ. School of Medicine, CA (United States). Dept. of Pathology
  3. Stanford Univ. School of Medicine, CA (United States). Dept. of Pathology; Stanford Health Care and Stanford Children’s Health, Palo Alto, CA (United States)
  4. Cepheid, Solna (Sweden)
  5. Cepheid, Sunnyvale, CA (United States)
  6. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  7. Univ. of Texas Medical Branch, Galveston, TX (United States)
  8. Public Health Agency of Canada, Winnipeg, MB (Canada)
  9. Public Health Agency of Canada, Winnipeg, MB (Canada)
  10. Public Health Agency of Sweden, Solna (Sweden)

The recently developed Xpert® Ebola Assay is a novel nucleic acid amplification test for simplified detection of Ebola virus (EBOV) in whole blood and buccal swab samples. The assay targets sequences in two EBOV genes, lowering the risk for new variants to escape detection in the test. The objective of this report is to present analytical characteristics of the Xpert® Ebola Assay on whole blood samples. Our study evaluated the assay’s analytical sensitivity, analytical specificity, inclusivity and exclusivity performance in whole blood specimens. EBOV RNA, inactivated EBOV, and infectious EBOV were used as targets. The dynamic range of the assay, the inactivation of virus, and specimen stability were also evaluated. The lower limit of detection (LoD) for the assay using inactivated virus was estimated to be 73 copies/mL (95% CI: 51–97 copies/mL). The LoD for infectious virus was estimated to be 1 plaque-forming unit/mL, and for RNA to be 232 copies/mL (95% CI 163–302 copies/mL). The assay correctly identified five different Ebola viruses, Yambuku-Mayinga, Makona-C07, Yambuku-Ecran, Gabon-Ilembe, and Kikwit-956210, and correctly excluded all non-EBOV isolates tested. The conditions used by Xpert® Ebola for inactivation of infectious virus reduced EBOV titer by ≥6 logs. In conclusion, we found the Xpert® Ebola Assay to have high analytical sensitivity and specificity for the detection of EBOV in whole blood. It offers ease of use, fast turnaround time, and remote monitoring. The test has an efficient viral inactivation protocol, fulfills inclusivity and exclusivity criteria, and has specimen stability characteristics consistent with the need for decentralized testing. The simplicity of the assay should enable testing in a wide variety of laboratory settings, including remote laboratories that are not capable of performing highly complex nucleic acid amplification tests, and during outbreaks where time to detection is critical.

Research Organization:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
Sponsoring Organization:
USDOE; Bill and Melinda Gates Foundation
Grant/Contract Number:
AC52-07NA27344
OSTI ID:
1259525
Alternate ID(s):
OSTI ID: 1474356
Journal Information:
PLoS ONE, Journal Name: PLoS ONE Journal Issue: 11 Vol. 10; ISSN 1932-6203
Publisher:
Public Library of ScienceCopyright Statement
Country of Publication:
United States
Language:
English

References (26)

Ebola Virus Epidemiology, Transmission, and Evolution during Seven Months in Sierra Leone journal June 2015
Identification of essential outstanding questions for an adequate European laboratory response to Ebolavirus Zaire West Africa 2014 journal January 2015
Ebola and Marburg haemorrhagic fever journal March 2015
Serology and cytokine profiles in patients infected with the newly discovered Bundibugyo ebolavirus journal February 2012
Rapid diagnostics for Ebola in emergency settings journal August 2015
Genetic diversity and evolutionary dynamics of Ebola virus in Sierra Leone journal May 2015
Shedding of Ebola Virus in an Asymptomatic Pregnant Woman journal June 2015
Assessment of the Risk of Ebola Virus Transmission from Bodily Fluids and Fomites journal November 2007
High‐Throughput Molecular Detection of Hemorrhagic Fever Virus Threats with Applications for Outbreak Settings journal November 2007
Risk of Misinterpretation of Ebola Virus PCR Results After rVSV ZEBOV–GP Vaccination journal February 2015
Genomic surveillance elucidates Ebola virus origin and transmission during the 2014 outbreak journal August 2014
Reidentification of Ebola Virus E718 and ME as Ebola Virus/H.sapiens-tc/COD/1976/Yambuku-Ecran journal November 2014
First International Quality Assurance Study on the Rapid Detection of Viral Agents of Bioterrorism journal April 2004
Rapid Diagnosis of Ebola Hemorrhagic Fever by Reverse Transcription-PCR in an Outbreak Setting and Assessment of Patient Viral Load as a Predictor of Outcome journal March 2004
Technology for Automated, Rapid, and Quantitative PCR or Reverse Transcription-PCR Clinical Testing journal May 2005
Nomenclature- and Database-Compatible Names for the Two Ebola Virus Variants that Emerged in Guinea and the Democratic Republic of the Congo in 2014 journal November 2014
Discussions and decisions of the 2012–2014 International Committee on Taxonomy of Viruses (ICTV) Filoviridae Study Group, January 2012–June 2013 journal October 2013
ReEBOV Antigen Rapid Test kit for point-of-care and laboratory-based testing for Ebola virus disease: a field validation study journal August 2015
Live attenuated recombinant vaccine protects nonhuman primates against Ebola and Marburg viruses journal June 2005
Ebola virus: from discovery to vaccine journal August 2003
Shedding of Ebola Virus in an Asymptomatic Pregnant Woman journal June 2015
Physicochemical inactivation of Lassa, Ebola, and Marburg viruses and effect on clinical laboratory analyses. journal January 1984
First International Quality Assurance Study on the Rapid Detection of Viral Agents of Bioterrorism journal April 2004
Rapid Diagnosis of Ebola Hemorrhagic Fever by Reverse Transcription-PCR in an Outbreak Setting and Assessment of Patient Viral Load as a Predictor of Outcome journal March 2004
Reidentification of Ebola Virus E718 and ME as Ebola Virus/H.sapiens-tc/COD/1976/Yambuku-Ecran journal November 2014
Comprehensive Panel of Real-Time TaqMan™ Polymerase Chain Reaction Assays for Detection and Absolute Quantification of Filoviruses, Arenaviruses, and New World Hantaviruses journal May 2010

Cited By (14)

Responding to ever-changing epidemiological dynamics of Ebola virus disease journal November 2016
Establishing Ebola Virus Disease (EVD) diagnostics using GeneXpert technology at a mobile laboratory in Liberia: Impact on outbreak response, case management and laboratory systems strengthening journal January 2018
The etiology of Ebola virus disease-like illnesses in Ebola virusnegative patients from Sierra Leone journal April 2016
Development of Mobile Laboratory for Viral Hemorrhagic Fever Detection in Africa text January 2018
Development and Evaluation of a Duo Zaire ebolavirus Real-Time RT-PCR Assay Targeting Two Regions within the Genome journal December 2019
Real-Time and End-Point PCR Diagnostics for Ebola Virus book June 2017
Translating RNA sequencing into clinical diagnostics: opportunities and challenges journal March 2016
Paper-based RNA detection and multiplexed analysis for Ebola virus diagnostics journal May 2017
Virus-encoded miRNAs in Ebola virus disease journal April 2018
Recent advances in the development and evaluation of molecular diagnostics for Ebola virus disease journal March 2019
Diagnosis and management of Ebola samples in the laboratory journal May 2016
Molecular Diagnostic Field Test for Point-of-Care Detection of Ebola Virus Directly From Blood journal September 2016
Pan-filovirus one-step reverse transcription-polymerase chain reaction screening assay preprint March 2019
Diagnosis of Ebola Virus Disease: Past, Present, and Future journal July 2016