Impact of Respiratory Syncytial Virus Subtype and Viral Load on the Clinical Course and Disease Severity of Acute Respiratory Tract Infection in Hospitalized Children

Background: Respiratory syncytial virus (RSV) is a leading cause of hospitalization in children. The impact of viral factors like RSV subtype and viral load (VL) on disease severity remains unclear. Methods: We screened 1171 hospitalized children ≤3 years of age with respiratory symptoms in winter seasons (2017–2020) for RSV infection by Reverse Transcription Polymerase Chain reaction. Disease severity was assessed using length of hospital stay and a previously validated disease severity score (