We sequenced 54 respiratory syncytial virus (RSV) genomes collected during 2021-22 and 2022-23 outbreaks in Washington, USA, to determine the origin of increased RSV cases. Detected RSV strains have been spreading for >10 years, suggesting a role for diminished population immunity from low RSV exposure during the COVID-19 pandemic.
Keywords: COVID-19; SARS; SARS-CoV-2; United States; Washington; coronavirus; coronavirus disease; evolution; genome; genotype; human orthopneumovirus; respiratory infections; respiratory syncytial virus; severe acute respiratory syndrome coronavirus 2; viruses; zoonoses.