title: First international external quality assessment of molecular diagnostics for Mers-CoV.
abstract: BACKGROUND
  Since the discovery of Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012, diagnostic protocols were quickly published and deployed globally.
  
  
  OBJECTIVE
  We set out to assess the quality of MERS-CoV molecular diagnostics worldwide.
  
  
  METHODS
  Both sensitivity and specificity were assessed using 12 samples containing different viral loads of MERS-CoV or common coronaviruses (OC43, 229E, NL63, HKU1).
  
  
  RESULTS
  The panel was sent to more than 106 participants, of which 99 laboratories from 6 continents returned 189 panel results.Scores ranged from 100% (84 laboratories) to 33% (1 laboratory). 15% of respondents reported quantitative results, 61% semi-quantitative (Ct-values or time to positivity) and 24% reported qualitative results. The major specific technique used was real-time RT-PCR using the WHO recommended targets upE, ORF1a and ORF1b. The evaluation confirmed that RT-PCRs targeting the ORF1b are less sensitive, and therefore not advised for primary diagnostics.
  
  
  CONCLUSIONS
  The first external quality assessment MERS-CoV panel gives a good insight in molecular diagnostic techniques and their performances for sensitive and specific detection of MERS-CoV RNA globally. Overall, all laboratories were capable of detecting MERS-CoV with some differences in sensitivity. The observation that 8% of laboratories reported false MERS-CoV positive single assay results shows room for improvement, and the importance of using confirmatory targets.
authors.affiliation: Department of Viroscience, Erasmus MC, Rotterdam, The Netherlands.
authors.forename: Suzan D
authors.initials: SD
authors.lastname: Pas
authors.affiliation: Center for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany.
authors.forename: Pranav
authors.initials: P
authors.lastname: Patel
authors.affiliation: Department of Viroscience, Erasmus MC, Rotterdam, The Netherlands.
authors.forename: Chantal
authors.initials: C
authors.lastname: Reusken
authors.affiliation: Center for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany.
authors.forename: Cristina
authors.initials: C
authors.lastname: Domingo
authors.affiliation: Institute for virology, University of Bonn, Bonn, Germany; German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany.
authors.forename: Victor M
authors.initials: VM
authors.lastname: Corman
authors.affiliation: Institute for virology, University of Bonn, Bonn, Germany; German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Drosten
authors.affiliation: Federal Institute of Virology and Immunology, Berne and Mittelhäusern, Switzerland; Vetsuisse Faculty, University of Berne, Switzerland.
authors.forename: Ronald
authors.initials: R
authors.lastname: Dijkman
authors.affiliation: Federal Institute of Virology and Immunology, Berne and Mittelhäusern, Switzerland; Vetsuisse Faculty, University of Berne, Switzerland.
authors.forename: Volker
authors.initials: V
authors.lastname: Thiel
authors.affiliation: Department of Microbiology and Immunology, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman; Institute of Virology, University of Veterinary Medicine Vienna, Vienna, Austria.
authors.forename: Norbert
authors.initials: N
authors.lastname: Nowotny
authors.affiliation: Department of Viroscience, Erasmus MC, Rotterdam, The Netherlands.
authors.forename: Marion P G
authors.initials: MP
authors.lastname: Koopmans
authors.affiliation: Center for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany. Electronic address: niedrigm@rki.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Niedrig
mesh_terms: D018352:Coronavirus Infections / Q000175:diagnosis* / Q000821:virology; D006801:Humans; D038622:Internationality; D059021:Laboratory Proficiency Testing; D065207:Middle East Respiratory Syndrome Coronavirus / Q000235:genetics / Q000302:isolation & purification*; D025202:Molecular Diagnostic Techniques / Q000592:standards*; D060888:Real-Time Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D019562:Viral Load
keywords: Diagnosis; EQA; MERS-CoV; Molecular; QPCR; Quality control; Real-time RT-PCR; Viral load