Sugaya N, et al. - The vaccine effectiveness (VE) of inactivated influenza vaccine (IIV) was assessed in children 6 months to 15 years of age in 2015/16 season. Researchers also estimated the three-season VE in preventing influenza illness and hospitalization, based on the data obtained during the three seasons from 2013 to 2016. Based on much larger numbers of children than previous studies, VE in preventing illness as well as VE in preventing hospitalization was demonstrated in this present study.