Genomic Diversity of Human Respiratory Syncytial Virus (HRSV) Type A in a Pediatric Cohort in the United States After the Onset of the COVID-19 Pandemic
TL;DR
It is suggested that post-pandemic HRSV circulation was associated with changes in viral population dynamics and genetic diversity, emphasizing the value of continued genomic surveillance to monitor viral evolution and support future prevention strategies.
Abstract
Human Respiratory Syncytial Virus (HRSV) is a leading cause of respiratory infections in young children. HRSV cases declined dramatically in the initial stages of the COVID-19 pandemic, followed by a resurgence in 2022/2023. To investigate patterns of viral genetic diversity and evolutionary dynamics during this period, HRSV sequences were analyzed at national and global levels, including newly sequenced samples from pediatric patients at a major Florida medical center in Alachua County. Our Florida strains clustered within multiple clades, with no clear association between specific clades and clinical or epidemiologic characteristics. Phylodynamic analyses suggested post-pandemic changes in HRSV-A and HRSV-B population dynamics, while phylogeographic patterns were compatible with possible viral introductions from European countries. We also detected amino acid diversity in known G-protein epitope regions, indicating a genetic variation in antigenically relevant sites. These findings suggest that post-pandemic HRSV circulation was associated with changes in viral population dynamics and genetic diversity, emphasizing the value of continued genomic surveillance to monitor viral evolution and support future prevention strategies.