Analysis of etiological and epidemiolical characteristics of upper respiratory infection among preschool children in Shenyang

Abstract

Objective To elucidate the pathogenic spectrum of upper respiratory infections among preschool children in Shenyang area from October 2016 to September 2017, so as to provide scientific basis for prevention and control of respiratory tract infections among childrens. Methods From October 2016 to September 2017, the epidemiological information of the acute upper respiratory tract infection cases in the outpatient section of Shenyang children's Hospital in Liaoning province were collected from the Chinese National Notifiable Infectious Disease Reporting System. Nasopharyngeal swab specimens of the cases were collected to detect nucleic acid respiratory viruses by multiple fluorescent real-time RT-PCR (reverse transcription polymerase chain reaction). The differences of the positive detection rates among cases with various features, virus types and sampling time were analyzed by chi-squared test. Results At least one type of pathogen was detected in 126 out of 218 outpatient children, the overall positive rate was 57.8%. The differences among positive rates of the viruses were statistically significant (x2=230.07, P<0.01). The positive rate of influenza virus A (FluA) was the highest (18.4%, 40/218), followed by enterovirus (EV) with a positive rate of 17.0% (37/218). The differences among the positive rates of FluA and EV in different seasons were statistically significant (x2 values were 37. 21 and 9.01, respectively, and both P values were <0.01). The differences among positive rates in children of different ages were statistically significant (x2=11.68, P=0.003) . The highest was 67.4% (60/89) in 4-7 years old group. More than 2 virus positive samples were detected in 34 samples, accounting for 27% (34/126) . Conclusions Influenza A virus and enterovirus were the main pathogens causing the upper respiratory infection among preschool children in Shenyang area, mainly in 4-7 years old group.The main pathogens of the seasons were different, e.g. influenza virus in winter and enterovirus in autumn. Key words: Preschool children; Respiratory tract infections; Viruses; Epidemiological characters