Clinical validation of a multiplex colorimetric RT-LAMP assay for simultaneous RSV-A and RSV-B detection in a real-world setting

Respiratory Syncytial Virus (RSV) is a leading cause of pediatric respiratory morbidity and hospitalization worldwide. We validated a multiplex colorimetric Reverse Transcription Loop-Mediated Isothermal Amplification (mRT-LAMP) assay targeting the conserved nucleocapsid (N) encoding-gene for the detection of RSV-A and RSV-B. In 90 clinical specimens, the assay demonstrated 100% specificity and a diagnostic sensitivity of 86.1% with robust performance in samples with higher viral loads effectively identifying individuals during the most contagious phase of the infections. Well-suited for point-of-care diagnostics and surveillance in resource-limited settings, this tool establishes an epidemiological baseline crucial for managing future emergencies and assessing immunization impacts.