Epidemiological characteristics of children’s respiratory tract viral infection in Chongqing during 2009 and 2011

Abstract:

Objective：To discuss epidemiological characteristics and pathogenic condition of common respiratory tract viral infection in hospitalized children in Chongqing. Methods：Totally 19 452 patients hospitalized in respiratory ward from 2009 to 2011 were retro－spectively analyzed. Direct immunofluorescent method was used to detect seven common respiratory viruses in nasopharyngeal secre－tions including respiratory syncytial virus（RSV），adenovirus（ADV），influenza virus A（IVA），influenza virus B（IVB） and parainfluen－za virus（PIV）. Epidemiological data and diseases caused by viruses in 2009 were analyzed retrospectively. Results：（1）Positive rates of each virus were RSV 29.23%，ADV 3.98%，IVA 2.54%，IVB 0.47%，PIV1 1.94%，PIV2 0.25%，PIV3 9.83%. （2）Peak periods of RSV infection were December and January. Both PIV3 and ADV were common from April to July. （3）Statistics results of virus infection of different genders（ ?字2=75.014，P=0.000），ages（ ?字2=1 011.396，P=0.000） and seasons（ ?字2=1 070.282，P=0.000） became statistically sig－nificant. （4）In 2009，RSV，PIV3 and IVA were the top 3 viruses among pneumonia，bronchiolitis，bronchitis and laryngotracheobron－chitis children；ADV，IVA and PIV3 were the top 3 viruses in the upper respiratory infection children. （5）In 4 810 pneumonia cases，severe pneumonia were 268 cases and its virus positive rate was 60.07%. Statistics results of virus infection rate between common pneumonia and severe pneumonia were statistically significant（ ?字2=51.160，P=0.000）. Conclusions：（1）Virus was still the main pathogen of respiratory infection disease. RSV still took the first place of viral pathogens，followed by PIV3 and ADV. （2）RSV are com－mon in autumn and winter while ADV and PIV3 are common in spring and summer. （3）Virus infections are relevant with gender，age and season. （4）RSV，PIV3 and IVA are the main viral pathogens in the lower respiratory infection. ADV，IVA and PIV3 are the main viral pathogens in the upper respiratory infection. （5）Virus positive rate and RSV positive rate of severe pneumonia are higher than those of common pneumonia.