Clinical performance evaluation of the Fluorecare® SARS-CoV-2 & Influenza A/B & RSV rapid antigen combo test in symptomatic individuals

J Clin Virol. 2023 Apr:161:105419. doi: 10.1016/j.jcv.2023.105419. Epub 2023 Feb 28.

Abstract

Background: A SARS-CoV-2+Flu A/B+RSV Combo Rapid test may be more relevant than Rapid Antigen Diagnostic (RAD) tests targeting only SARS-CoV-2 since we are facing a concurrent circulation of these viruses during the winter season.

Objectives: To assess the clinical performance of a SARS-CoV-2+Flu A/B+RSV Combo test in comparison to a multiplex RT-qPCR.

Study design: Residual nasopharyngeal swabs issued from 178 patients were included. All patients, adults and children, were symptomatic and presented at the emergency department with flu-like symptoms. Characterization of the infectious viral agent was done by RT-qPCR. The viral load was expressed as cycle threshold (Ct). Samples were then tested using the multiplex RAD test Fluorecare®ฏ SARS-CoV-2 & Influenza A/B & RSV Antigen Combo Test. Data analysis was carried out using descriptive statistics.

Results: The sensitivity of the test varies according to the virus, with the highest sensitivity observed for Influenza A (80.8.% [95%CI: 67.2 - 94.4]) and the lowest sensitivity observed for RSV (41.5% [95%CI: 26.2 - 56.8]). Higher sensitivities were observed for samples with high viral loads (Ct < 20) and decrease with low viral loads. The specificity for SARS-CoV-2, RSV and Influenza A and B was >95%.

Conclusions: The Fluorecare® combo antigenic presents satisfying performance in real-life clinical setting for Influenza A and B in samples with high viral load. This could be useful to allow a rapid (self-)isolation as the transmissibility of these viruses increase with the viral load. According to our results, its use to rule-out SARS-CoV-2 and RSV infection is not sufficient.

Keywords: Antigen; Combo; Influenza; Multiplex; RAD; RSV; SARS-CoV-2.

MeSH terms

  • Adult
  • COVID-19* / diagnosis
  • Child
  • Humans
  • Immunologic Tests
  • Influenza, Human* / diagnosis
  • Respiratory Syncytial Virus Infections* / diagnosis
  • SARS-CoV-2
  • Sensitivity and Specificity