European multicenter evaluation of Xpert® Xpress SARS-CoV-2/Flu/RSV test

J Med Virol. 2021 Oct;93(10):5798-5804. doi: 10.1002/jmv.27111. Epub 2021 Jun 6.

Abstract

Rapid diagnostics for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are paramount for reducing the spread of the current pandemic. During additional seasonal epidemics with influenza A/B and respiratory syncytial virus (RSV), the clinical signs and symptoms cannot be distinguished easily from SARS-CoV-2. Therefore, a new assay combining four targets in the form of the new Xpert Xpress SARS-CoV-2/Flu/RSV assay was evaluated. The assay was compared to the Xpert Xpress SARS-CoV-2, Xpert Xpress Flu/RSV, Seegene Flu/RSV, influenza A/B r-gene® and RSV/hMPV r-gene®. A total of 295 nasopharyngeal and throat swabs were tested at four institutes throughout Europe including 72 samples positive for SARS-CoV-2, 65 for influenza A, 47 for influenza B, and 77 for RSV. The sensitivity of the new assay was above 95% for all targets, with the highest for SARS-CoV-2 (97.2%). The overall correlation of SARS-CoV-2 Ct values between Xpert Xpress SARS-CoV-2 assay and Xpert Xpress SARS-CoV-2/Flu/RSV assay was high. The agreement between Ct values above 30 showed the multiplex giving higher Ct values for SARS-CoV-2 on average than the singleplex assay. In conclusion, the new assay is a rapid and reliable alternative with less hands-on time for the detection of not one, but four upper respiratory tract pathogens that may circulate at the same time.

Keywords: COVID-19; SARS-CoV-2; influenza; multiplex PCR; pandemic; respiratory syncytial virus.

Publication types

  • Evaluation Study
  • Multicenter Study

MeSH terms

  • COVID-19 / diagnosis
  • COVID-19 Nucleic Acid Testing
  • Europe / epidemiology
  • Humans
  • Influenza A virus / isolation & purification*
  • Influenza B virus / isolation & purification*
  • Influenza, Human / diagnosis
  • Molecular Diagnostic Techniques
  • Multiplex Polymerase Chain Reaction
  • Nasopharynx / virology
  • Respiratory Syncytial Virus Infections / diagnosis
  • Respiratory Syncytial Virus, Human / isolation & purification*
  • Respiratory Tract Infections / diagnosis*
  • Respiratory Tract Infections / virology
  • SARS-CoV-2 / genetics
  • SARS-CoV-2 / isolation & purification*
  • Sensitivity and Specificity