Recent Outbreak Features of Childhood Influenza at A Single Community Hospital

Purpose: Several seasonal domestic influenza epidemics have been reported but not nowadays. I did this study to know its update epidemiological features. Methods: I collected the epidemiological and demographic informations of influenza patients who had visited and been diagnosed at the Department of Pediatrics , Yogin Severance Hospital from January 2014 to May 2016. Influenza infection was detected by rapid antigen assay They were studied and compared with each other with multiple parameters mentioned above. Results: There were 579 cases and its epidemic started in January and ended in March (2014) or April (2015, 2016) and peak month was February (48.9%). Their mean age was 6.5±4.0 years old and male to female ratio was 1.2:1. Two hundred and eighty five cases (49.2%) were 6 years old and over. Their accumulative monthly ages increased continuously by month from 4.6±3.3 years old in January to 7.4±4.3 years old in April ( P <0.001). The monthly ages in 2016 were significantly different among them each other, not but between on March and on April. The age in January 2016 was significantly different from that of February and March in 2015. Age difference was also observed between that in February 2014 and January 2016 as well as March in 2014 and 2016. Yearly case numbers of influenza A and B were 107 and 55 in 2014, 89 and 38 in 2015, and 139 and 151 in 2016, respectively. The component ratio of influenza B in 2016 is increased when comparing with that in 2014 ( P =0.002) and 2015 ( P