Multi-center evaluation of the cobas® Liat® Influenza A/B & RSV assay for rapid point of care diagnosis

Abstract

Point of Care Testing (POCT) provides the capability for rapid laboratory test results in patient care environments where a traditional clinical laboratory is not available. POCTs have shorter turn-around times (TATs), they may be performed by non-laboratory personnel, and the need for transport time is eliminated. The Food and Drug Administration (FDA) recently granted Clinical Laboratory Improvements Amendment (CLIA) waiver status to the cobas® Influenza A/B & RSV assay, a rapid, accurate point-of-care test for Influenza and respiratory syncytial virus (RSV) performed on the Liat® System. The performance characteristics of this test were determined though a multi-site study consisting of different point of care testing environments. Prospectively collected Nasopharyngeal (NP) swabs from 1361 patients seen at 8 primary care clinics and 4 emergency departments (EDs) and 295 retrospectively identified specimens were tested for Influenza A/B and RSV on the cobas® Liat® platform. Performance characteristics were determined through comparison to ProFlu+, a laboratory-based PCR test for Influenza A/B and RSV (reference test). Discordant specimens were adjudicated following bi-directional sequencing. The cobas® Influenza A/B and RSV assay showed sensitivities of 99.6%, 99.3%, and 96.8% for Influenza A, Influenza B, and RSV, respectively as determined from percent positive agreement (PPA) following comparison to the reference test. Sequencing confirmed cobas® Influenza A/B and RSV results in 49.2% of reference test discordant specimens, while crossing threshold data suggest increased sensitivity compared to the reference test. The cobas® Influenza A/B and RSV assay was found to be a rapid, sensitive POCT for the detection of these viruses, and provides laboratory-quality PCR-based diagnostic results in point of care settings.