Circulation Pattern and Genetic Variation of Rhinovirus Infection among Hospitalized Children on Hainan Island, before and after the Dynamic Zero-COVID Policy, from 2021 to 2023

Objective: Throughout the COVID-19 pandemic, Rhinovirus (RV) remained notable persistence, maintaining its presence while other seasonal respiratory viruses were largely suppressed by pandemic restrictions during national lockdowns. This research explores the epidemiological dynamics of RV infections among pediatric populations on Hainan Island, China, specifically focusing on the impact before and after the zero-COVID policy was lifted. Methods: From January 2021 to December 2023, 19,680 samples were collected from pediatric patients hospitalized with acute lower respiratory tract infections (ARTIs) at the Hainan Maternal and Child Health Hospital. The infection of RV was detected by tNGS. RV species and subtypes were identified in 32 RV-positive samples representing diverse time points by analyzing the VP4/VP2 partial regions. Results: Among the 19,680 pediatric inpatients with ARTIs analyzed, 21.55% were found to be positive for RV infection, with notable peaks observed in April 2021 and November 2022. A gradual annual decline in RV infections was observed, alongside a seasonal pattern of higher prevalence during the colder months. The highest proportion of RV infections was observed in the 0-1 year age group. Phylogenetic analysis revealed 23 distinct RV subtypes, with a shift in dominance from RV-A to RV-C in 2022, suggesting evolving RV dynamics. Conclusions: The research emphasizes the necessity for ongoing surveillance and targeted management, particularly for populations highly susceptible to severe illnesses caused by RV infections.