2023-2025年岳阳市儿童呼吸道合胞病毒感染分子流行特征OA

Objective To analyze the epidemiological characteristics,types,and genotypes of respiratory syncytial virus(RSV)infection in children in Yueyang city.Methods A total of 9,690 children with acute respiratory tract infection ad-mitted to the outpatient and inpatient departments of Yueyang Maternal and Child Health Hospital from April 2023 to Au-gust 2025 were selected as study participants.A total of 9,690 nasopharyngeal swab samples were collected from the chil-dren for targeted sequencing to identify RSV genotypes,and the results were analyzed in combination with clinical data.Re-sults There were 1,435 RSV-positive samples,including 562 RSV A-positive samples and 854 RSV B-positive samples,and 19 samples positive for both subtypes.From 2023 to 2025,the differences in the positive rates of RSV,RSV A,and RSV B in samples collected in different years were statistically significant(P<0.05).In 2023,RSV A was the predominant circulating subtype;in 2024,RSV B was predominant;in 2025,RSV A and RSV B co-circulated.The differences in the positive rates of RSV,RSV A,and RSV B in samples from different age groups were statistically significant(P<0.05).The positive rates of RSV and its two subtypes in samples showed a decreasing trend with increasing age of the children.The RSV positive rate in samples from children aged 1 year and under was 18.35%,accounting for 63.62%(913/1,435)of all RSV-positive samples.The differences in the positive rates of RSV A,RSV B,RSV A+RSV B,and RSV in samples collected in different seasons were statistically significant(P<0.05).The highest RSV positive rate was observed in sam-ples collected in spring(27.01%),followed by winter(19.07%).RSV A was prevalent in spring,while RSV B had two peaks(spring and winter).In addition,co-infection of RSV A or RSV B with human cytomegalovirus(HCMV)was a com-mon dual viral co-infection.In terms of clinical diagnosis,the proportion of severe pneumonia among RSV A-positive chil-dren was higher than that among RSV B-positive children(P<0.05).A total of 36 samples were randomly selected from the RSV-positive samples for sequencing,of which 34 were successfully sequenced.Among them,all 20 RSV A subtype samples were the ON1 genotype,and all 14 RSV B subtype samples were the BA9 genotype.Conclusion In the Yueyang area,RSV A and RSV B can circulate either predominantly or concurrently;ON1 and BA9 are the predominant epidemic genotypes.Children aged 1 year and under are at high risk for RSV infection.RSV remains highly prevalent in spring and winter;co-infection is common.RSV A may be associated with more severe clinical outcomes.