Compared with RSV, FluA (OR 5.69) and HRV (OR 3.29) infections were strongly associated with being ≥ 3 years old among pediatric cases post-pandemic.
Cohort (n=19,900)
No
Post-pandemic age redistribution of pediatric respiratory viruses differed by pathogen, with FluA shifting toward older children while RSV remained concentrated in early childhood.
Odds Ratio: 5.69
BACKGROUND: Whether age distributions of common pediatric respiratory viruses changed uniformly after the COVID‑19 pandemic remains unclear. Understanding pathogen‑specific patterns is important for guiding surveillance and prevention strategies in the post‑pandemic period. METHODS: We conducted a retrospective hospital‑based cohort study of 19,900 laboratory‑confirmed single‑virus infection episodes caused by RSV, influenza A virus (FluA), and human rhinovirus (HRV) among children aged 0-17 years who presented to a provincial women's and children's hospital in China from 2022 to 2025. These data describe age distributions among detected cases and do not represent population‑level incidence. Age distributions were examined using kernel density estimation and quantile regression. Annual proportions of children aged ≥ 3 years were compared across pathogens and years, and multivariable logistic regression was used to assess adjusted associations with older age. Sensitivity analyses included outpatient‑only models, RSV‑only models, and an alternative age cutoff of ≥ 5 years. RESULTS: RSV infections occurred mainly in the youngest children (median 1.4-2.6 years), FluA affected older children (median up to 5.9 years), and HRV showed a stable intermediate pattern (median 2.9-3.5 years). FluA demonstrated clear shifts toward older ages in 2023 and 2025, whereas RSV showed only modest variation and HRV remained stable across years. Compared with RSV, FluA (OR 5.69) and HRV (OR 3.29) were strongly associated with being ≥ 3 years old. Findings were consistent across all sensitivity analyses. CONCLUSIONS: Age redistribution after the pandemic differed by pathogen. FluA shifted toward older children, RSV remained concentrated in early childhood, and HRV returned to a stable pre‑pandemic profile. These. results highlight the value of pathogen‑specific, age‑stratified approaches to pediatric respiratory virus surveillance in the post‑pandemic era.
Hongbo Hu (Wed,) conducted a cohort in RSV, influenza A, and rhinovirus infections (n=19,900). Influenza A (FluA) infection vs. RSV infection was evaluated on Being ≥ 3 years old (OR 5.69). Compared with RSV, FluA (OR 5.69) and HRV (OR 3.29) infections were strongly associated with being ≥ 3 years old among pediatric cases post-pandemic.