[Pathogenic investigation of human respiratory syncytial virus infection in kindergarten children in Tongzhou District, Beijing City in 2023].

The study focused on individuals with influenza-like symptoms (fever, cough, sore throat, runny nose, and other respiratory symptoms) in three kindergartens in Tongzhou District, Beijing City, in April 2023. Nasopharyngeal swab specimens were collected, and real-time fluorescent quantitative PCR was used to detect common respiratory pathogens in the collected specimens. Positive specimens were subjected to sequencing analysis of the highly variable region of human respiratory syncytial virus (HRSV) G protein, homology analysis and phylogenetic tree analysis. A total of 25 fever cases were collected from 3 kindergartens, aged 3-8 years old, with an age M (Q1, Q3) of 4 (3.5, 5) years old. Ten confirmed cases of HRSV positive were screened and detected using the fluorescent quantitative PCR method, with a total detection rate of 40% (10/25). Typing identification and sequencing analysis confirmed that the main epidemic type was HRSV subtype B, which was highly homologous and closely related to previous epidemic strains in the region. Through pathogen investigation and analysis, it was preliminarily determined that this epidemic was dominated by HRSV subtype B.