Tracking RSV Evolution and Treatment Resistance Through Genomic Surveillance

The Minnesota Department of Health recently expanded its viral genomic surveillance program expanded to include human respiratory syncytial virus (RSV). This initiative aims to track genetic diversity and investigate viral circulation dynamics using whole-genome sequencing (WGS). In addition, researchers hope to use this data to detect emerging mutations that could affect treatment and vaccine efficacy.

Researchers collected 575 RSV-positive specimens from 11 health care facilities in Minnesota between July 2023 and February 2024. Genomes were sequenced using the GridION platform and analyzed using the nf-core Viralrecon pipeline with Nextclade software for genome subgrouping. Two hundred eighty-seven genomes were classified as subgroup RSV-A and 288 as subgroup RSV-B.

RSV-A showed greater diversity, while RSV-B genomes were less diverse, with the majority (91.5%) belonging to a single lineage. Phylogenetic analyses indicated RSV-A lineages diverged between 2 to 8 years before sample collection. Researchers identified 23 clusters of identical genomes, with 19.5% of samples showing identical nucleotide sequences. They also discovered a clade of RSV-B with the K68N mutation associated with resistance to nirsevimab, a monoclonal antibody treatment for RSV. This clade’s common ancestor is from September to November 2023, implying recent evolution and spread of resistance-associated mutations.

By integrating WGS with clinical data, Minnesota’s genomic surveillance program has the potential to become a valuable tool in RSV outbreak detection and intervention. Genomic surveillance of RSV can effectively reveal circulating viral lineages, clusters, and mutations tied to treatment resistance. Use of this data can help to monitor the virus’s evolution and its impact on RSV treatment and prevention strategies for the future.

Reference

Evans D, Kunerth H, Mumm E, et al. Genomic epidemiology of human respiratory syncytial virus, Minnesota, USA, July 2023-February 2024. Emerging Infectious Diseases. 2024;30(11):24214-2418. doi:10.3201/eid3011.241000