Epidemiological Characteristics Of Children’s Respiratory Tract Viral Infection In Chongqing During2009and2011

ObjectiveTo compare the epidemiological characteristics and pathogenic condition of common respiratory tract viral infection in hospitalized children in Chongqing.MethodsRetrospective analysis of19452cases admitted in the respiratory wards from January2009to December2011, was detected by direct immunofluorescence for seven common respiratory viruses in children’s nasopharyngeal secretions, which was took when they were hospitalized.The viruses included respiratory syncytial virus(RSV), adenovirus (ADV), influenza virus A, influenza virus B, parainfluenza virus1,2,3(PIV1,2,3).Results1.The total positive cases were9387, accounting for48.26%of all cases. The positive rates for7seven common respiratory viruses were RSV29.23%, ADV3.98%, IFA2.54%, IFBO.48%, PIV11.95%, PIV20.25%, PIV39.83%.2.The coinfection cases were604, and coinfection rate was3.11%. The cases of RSV combining with other viruses infection were516, accounting for85.43%(516/604), especially RSV+PIV3which were238accounting for39.40%(238/604) of all coinfection cases. The coinfection rate was high in November, December, January and February.3.The peak periods of RSV infection were in December and January, followed by November and February, and infection was lowest in May and June. PIV3were common in April, May, June to July. ADV had infection peak from April to July every year, May and June were the peak points, but it was rare in November and December. About influenza, IVA infection rate was2.54%(495/19452), IVB was0.47%(92/19452). PIV1was common from September to December in2009,and it was common from February to May during2010and2011.PIV2infections were common in September in2009, April in2010, March and August in2011.4.The Statistics results of virus infection of different gender, age and season became statistically significant.5.Among the6341cases in2009, the virus positive rate of bronchiolitis children was71.41%, and RSV was82.72%in the constituent ratio of virus. RSV, PIV3and IVA were the top3viruses among pneumonia, interstitial pneumonia, bronchiolitis, bronchitis and laryngotracheobronchitis children. ADV, IVA and PIV3were the top3 viruses in the upper respiratory infection children.Conclusions1. Virus was still the main pathogen of respiratory infection disease. Among the seven common respiratory viruses, RSV still took the first place of viral pathogen, PIV3and ADV followed up. The diminishing order of common respiratory viruses infection positive rate is RSV>PIV3>ADV>IVA>PIV1>IVB>PIV2.2.In coinfection, the great priority was the infection of RSV combining other viruses especially RSV+PIV3.3.RSV,ADV and PIV3had distinct regularities, RSV were common in autumn and winter while ADV and PIV3were common in spring and summer. The other4viruses had no distinct regularity.4.The virus infections were relevant to gender, age and season.5.RSV, PIV3and IVA were the main viral pathogens in the lower respiratory infection. ADV, IVA and PIV3were the main viral pathogens in the upper respiratory infection.