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Genomic and Molecular Characterisation of Respiratory Syncytial Virus in the National SARI Surveillance System Across Three Consecutive Seasons in North Macedonia (2022-2025)
Authors
Teodora Karevska
Institute for Public Health of the Republic of North Macedonia, Skopje
Golubinka Boshevska
Institute for Public Health of the Republic of North Macedonia, Skopje , Faculty of Medical Sciences, Goce Delchev University, Shtip
Elizabeta Jancheska
Institute for Public Health of the Republic of North Macedonia, Skopje
Maja Vukovikj
Institute for Public Health of the Republic of North Macedonia, Skopje
Senada Karishik
Institute for Public Health of the Republic of North Macedonia, Skopje
Gala Matevska
Institute for Public Health of the Republic of North Macedonia, Skopje
Gordana Nikolovska
Institute for Public Health of the Republic of North Macedonia, Skopje
Aneta Peshnachka
Institute for Public Health of the Republic of North Macedonia, Skopje
Dragan Kochinski
Institute for Public Health of the Republic of North Macedonia, Skopje
Kristina Stavridis
Institute for Public Health of the Republic of North Macedonia, Skopje
Enkela Polozhani
Institute for Public Health of the Republic of North Macedonia, Skopje
Milica Simova
Institute for Public Health of the Republic of North Macedonia, Skopje
Marija Andonovska
Institute for Public Health of the Republic of North Macedonia, Skopje
Gorica Popova
Faculty of Medical Sciences, Goce Delchev University, Shtip , PHI University Clinic for Respiratory Diseases in Children “Kozle”, Skopje
Icko Gjorgoski
Institute of Biology, Faculty of Natural Sciences and Mathematics, Ss.Cyril and Methodius University, Skopje
DOI:
https://doi.org/10.5644/ama2006-124.508
Keywords:
Respiratory Syncytial Virus, SARI, Genomic Surveillance, Whole-Genome Sequencing, Molecular Epidemiology
Abstract
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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