Direct Comparison of SARS-CoV-2 Analytical Limits of Detection across Seven Molecular Assays

J Clin Microbiol. 2020 Aug 24;58(9):e01535-20. doi: 10.1128/JCM.01535-20. Print 2020 Aug 24.


Analytical sensitivity for SARS-CoV-2 detection is a key performance metric for the evaluation of viral detection assays. We determined analytical limits of detection for seven SARS-CoV-2 assays using serial dilutions of pooled patient material quantified with droplet digital PCR. Limits of detection ranged from ≤10 to 74 copies/ml for commercial high-throughput laboratory analyzers (Roche Cobas, Abbott m2000, and Hologic Panther Fusion) and 167 to 511 copies/ml for sample-to-answer (DiaSorin Simplexa, GenMark ePlex) and point-of-care instruments (Abbott ID NOW). The CDC assay yielded limits of detection ranging from 85 to 499 copies/ml, depending on the extraction method and thermocycler used. These results can help to inform the assay choice for testing approaches to manage the current COVID-19 outbreak.

Keywords: SARS-CoV-2; limit of detection.

Publication types

  • Comparative Study

MeSH terms

  • Betacoronavirus / genetics*
  • COVID-19
  • COVID-19 Testing
  • Clinical Laboratory Techniques* / methods
  • Clinical Laboratory Techniques* / statistics & numerical data
  • Coronavirus Infections / diagnosis*
  • Coronavirus Infections / epidemiology
  • Humans
  • Limit of Detection
  • Molecular Diagnostic Techniques* / methods
  • Molecular Diagnostic Techniques* / statistics & numerical data
  • Pandemics
  • Pneumonia, Viral / diagnosis*
  • Pneumonia, Viral / epidemiology
  • RNA, Viral / analysis
  • RNA, Viral / genetics
  • SARS-CoV-2


  • RNA, Viral