海南岛2022～2023年住院儿童急性呼吸道感染中人偏肺病毒的分子流行病学与临床特征分析OA

Objective:To systematically characterize the epidemiological features of human metapneumovirus(HMPV)among pediatric inpatients with acute respiratory tract infections(ARTIs)on Hainan Island between 2022 and 2023,including in-fection rates,seasonal and age-related distribution,single versus co-infection patterns,clinical manifestations and risk factors for severe disease,and to assess the impact of China′s dynamic zero-COVID policy on HMPV circulation,thereby informing preci-sion control strategies.Methods:From January 2022 to December 2023,15 182 children(≤18 years)hospitalized with ARTIs at Hainan Women and Children′s Medical Center were enrolled.HMPV infection was detected by targeted next-generation sequenc-ing(tNGS),and partial sequencing of the fusion(F)protein gene was performed on 31 HMPV-positive samples to determine vi-ral genotypes and subtypes.Results:A total of 1 072 cases tested positive for HMPV(overall detection rate 7.06%),with the highest prevalence observed in the 3-7 year age group.The annual detection rate was 7.67%in 2022 and 6.75%in 2023.Notably,the HMPV epidemic peak shifted from spring 2022 to autumn 2023,indicating a significant alteration in seasonal circulation pat-terns.Co-infection with other respiratory pathogens showed no significant association with progression to severe disease.Phyloge-netic analysis identified four HMPV subtypes—B1,B2,A2c and A2b—with a major shift in May 2022:subtype A2c supplanted subtype B as the dominant strain and by 2023 accounted for the vast majority of cases,demonstrating dynamic evolution of HMPV lineages.Conclusion:On Hainan Island,HMPV exhibits dynamic subtype replacement and a notable shift in seasonal epidemic peaks.These findings underscore the necessity for sustained epidemiological surveillance and the development of targeted interven-tion strategies for high-risk pediatric populations.