Evaluation of novel second-generation RSV and influenza rapid tests at the point of care

• RSV FIA rapid testing provides highly sensitive diagnoses in pediatric acute care.
• Cycle threshold values <27 corresponded to sensitivities >80% fulfilling Food and Drug Administration criteria.
• Superficial nasal swabs were insignificantly less sensitive than nasopharyngeal.
• Parallel rapid testing for both flu and RSV is now feasible on the SOFIA™ platform.

Acute respiratory infections represent common pediatric emergencies. Infection control warrants immediate and accurate diagnoses. In the past, first-generation respiratory syncytial virus (RSV) rapid tests (strip tests) have shown suboptimal sensitivities. In 2013, the Food and Drug Administration licensed a second-generation RSV rapid test providing user-independent readouts (SOFIA™-RSV) using automated fluorescence assay technology known to yield superior results with influenza rapid testing. We are reporting the first point-of-care evaluation of the SOFIA™-RSV rapid test. In the Charité Influenza-Like Disease Cohort, 686 nasopharyngeal samples were tested in parallel with SOFIA™-RSV and SOFIA™-Influenza A + B. Compared to real-time PCR, SOFIA™-RSV sensitivities/specificities were 78.6%/93.9%, respectively (SOFIA™-Influenza A: 80.6%/99.3%). Performance was greatest in patients below 2 years of age with a test sensitivity of 81.8%. RSV sensitivities were highest (85%) in the first 2 days of illness and with nasopharyngeal compared to nasal swabs (P = 0.055, McNemar's test). Second-generation RSV and influenza rapid testing provides highly accurate results facilitating timely patient cohortation and management.