Molecular characterization of human rhinovirus strains detected in pediatric acute respiratory tract infections.

Background and Objectives: Acute respiratory tract infections (ARTI) are a leading cause of morbidity and mortality in children worldwide, accounting for approximately 18% of deaths in those <5 years of age. Viruses cause 50-90% of pediatric ARTI cases. Human rhinovirus (HRV) is increasingly associated with lower respiratory tract infections (LRTIs). This study aimed to detect HRV in pediatric ARTI cases and characterize circulating genotypes. Materials and Methods: Nasopharyngeal swabs from 154 children (≤5 years) presenting with ARTI were screened for HRV using real-time PCR. Thirteen samples with a cycle threshold ≤30 were sequenced. Phylogenetic analysis was performed using 41 global reference sequences representing different geographical regions and HRV types. Results: HRV was detected in 34.41% (53/154) of the samples. In children aged >1 month to 1 year, HRV positivity was significantly associated with severe acute respiratory infection (SARI) compared with influenza-like illness (ILI). Phylogenetic analysis revealed a predominance of HRV-C strains (n = 7), followed by HRV-A (n = 5) and HRV-B (n = 1). Conclusion: HRV was detected in a significant proportion of pediatric ARTI cases, with HRV-C as the predominant strain. Infants aged >1 month to 1 year showed a higher association with severe illness, underscoring the need for closer clinical monitoring in this age group.