The Study Of Clinical Features Of Human Respiratory Syncytial Virus In Hospitalized Children With Acute Lower Respiratory Tract Infections In Chongqing From 2013 To 2018

Background and objective:Respiratory syncytial virus(RSV)is the leading cause of respiratory infections in infants and young children worldwide.The previous research of our research group found that the RSV subtypes in Chongqing from 2006 to 2013 were alternately circulating with the law of “AABBAAB”.This study further tracked the prevalence of RSV,and analyzed the detection and clinical features of RSV in Chongqing from 2013 to 2018.It has certain clinical implications and provides clues for the molecul epidemiological study of RSV.Methods: The nasopharyngeal aspirate specimens(NPAs)was collected from the respiratory center of the Children's Hospital of Chongqing Medical University from June 2013 to December 2018 for respiratory symptoms and diagnosed as acute lower respiratory infection.The common respiratory viruses was detected and classificated by muti-PCR.We collected clinical data of children,using SPSS21.0 for statistical analysis.Results:1.RSV detection: From June 2013 to December 2018,3590 NPAs were collected,RSV detection rate was the highest(34.6%),and among RSV positive samples,675 were RSV-A positive(18.8 %),563 samples(15.7%)were positive for RSV-B,and 5(0.1%)were positive for both RSV-A and RSV-B.2.Circulation characteristics: RSV can be detected almost all year round,mainly from September to March next year.From 2013 to 2017,RSV-A and RSV-B follow the previous two-year alternating pattern,but after July 2017,the subtype A replaced the subtype B in advance to become the dominant subtype.3.Co-detection of other pathogens: 393 cases(393/1243,31.6%)of RSV were co-detected with viruses,of which HRV was the most common(217/1243,17.5%);558 cases(558/1243,44.9%)of RSV were detected with bacteria,the most common cases were detected by S.pneumoniae(162/1243,13.0%);a total of 54 cases(54/1243,4.3%)were detected with M.pneumoniae.4.Clinical features: RSV infection can cause fever,cough,wheezing,difficulty breathing and other symptoms.RSV combined with virus infection is more likely to cause wheezing(?2=9.680,P=0.021).Between two subtypes of RSV,RSV-A is more likely to cause fever,and there is no significant difference in disease severity.RSV-A is often associated with Haemophilus influenzae detected(P=0.044),RSV-B was more likely to be combined with IFV detection(P<0.001).Conclusion: RSV is the most common viral pathogen among in-patient children with acute lower respiratory infection in Chongqing from 2013 to 2018.The study also found no significant differences in disease severity caused by RSV-A and RSV-B,but fever is more common in RSV-A infected children.