Genomic and Molecular Characterisation of Respiratory Syncytial Virus in theNational SARI Surveillance System Across Three Consecutive Seasons in NorthMacedonia (2022-2025)
DOI:
https://doi.org/10.5644/ama2006-124.508Keywords:
Respiratory Syncytial Virus, SARI, Genomic Surveillance, Whole-Genome Sequencing, Molecular EpidemiologyAbstract
Objective. To describe the epidemiological, molecular, and genomic characteristics of respiratory syncytial virus (RSV) detected through the national severe acute respiratory infection (SARI) surveillance system in North Macedonia across three consecutive seasons (2022/2023-2024/2025).
Materials and Methods. This study analysed SARI surveillance data from seven hospital-based sentinel sites. RSV detection and subgroup determination were performed using reverse transcription quantitative polymerase chain reaction (RT-qPCR), following season-specific testing strategies, which should be considered when interpreting seasonal differences in RSV positivity. Consensus genomes were generated, and phylogenetic analyses were performed using contemporaneous European reference sequences. Amino acid substitutions in the G and F proteins were assessed descriptively.
Results. Among 1,899 laboratory-tested SARI cases, 53.3% were tested for RSV, of which 24.8% were positive. RSV-A predominated overall, although seasonal shifts in subgroup dominance were observed. RSV infections were concentrated among young children, particularly those aged 0-2 years. Whole-genome sequencing of 85 RSV-positive samples revealed a dynamic seasonal turnover of RSV-A lineages, whereas RSV-B circulation remained largely confined to a single dominant lineage across seasons. Analysis of antigenically important genes showed greater variability in the G gene compared with the more conserved F gene in both subgroups.
Conclusion. The integration of epidemiological, molecular, and whole-genome data within routine SARI surveillance provides a comprehensive overview of RSV circulation and evolution in North Macedonia. These findings contribute genomic data from an under-represented region and provide a foundation for future evaluation of RSV vaccination and mono- clonal antibody effectiveness by detecting viral genetic changes, should such measures be implemented in North Macedonia.
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Copyright (c) 2026 Teodora Karevska, Gorica Popova, Marija Andonovska, Milica Simova, Enkela Polozhani, Kristina Stavridis, Dragan Kochinski, Aneta Peshnachka, Gordana Nikolovska, Gala Matevska, Senada Karishik, Maja Vukovikj, Elizabeta Jancheska, Golubinka Boshevska, Icko Gjorgoski
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