Abstract
BACKGROUND: The prevalence of respiratory syncytial virus (RSV) caused acute lower respiratory tract infections (ALRTI) among children, which have made children susceptible to severe infection. This study aims to determine the prevalence of RSV among hospitalized children in Shenzhen, Guangdong Province, China, during the coronavirus disease 2019 (COVID-19) pandemic and examine any variation in molecular characteristics and clinical presentations. METHODS: Eligible children during the study period were retrospectively collected, and nasopharyngeal swabs were collected. RSV-positive samples were grouped into different subtypes using specific primers and into genotypes through sequencing of the second hypervariable region of the G gene. Clinical data, including demographic data, clinical presentations, laboratory and imaging results, were also collected from the medical records of these children. Those cases with COVID-19 antigen tests positive in this study were excluded, along with those involving mixed infections. RESULTS: Two hundred and seventeen (57.11%) of the 380 samples tested positive for RSV. Sequencing was successful in 51 of the samples, of which 27 belonged to RSV-A and 24 to RSV-B. Phylogenetic analysis of the 51 successfully sequenced RSV isolates revealed that all RSV-A strains were ON1 genotype, while all RSV-B strains were BA9. RSV-A ON1 genotype and RSV-B BA9 genotype stratified data showed that RSV-A subtype ON1 infection children were more likely to have longer hospital length of stay (P=0.04) and higher risk of pediatric intensive care unit (PICU) admission (P=0.008). CONCLUSIONS: During June 2021 to September 2021 in Shenzhen, Guangdong Province, China, RSV-A ON1 genotype was predominantly prevalent. RSV-A subtype ON1 infected children had longer hospital stays and higher PICU admission risk. Further studies are needed to explore the relationship between molecular biological features and clinical presentation.