[1] Osaka City Univ, Grad Sch Med, Dept Publ Hlth, Osaka 5458585, Japan
[2] Osaka City Univ, Grad Sch Med, Res Ctr Infect Dis Sci, Osaka 5458585, Japan
[3] Osaka Inst Publ Hlth, Dept Virol, Osaka 5370025, Japan
[4] Fujioka Pediat Clin, Tondabayashi 5840074, Japan
[5] Matsushita Kids Clin, Kadoma, Osaka 5710030, Japan
[6] Kubota Childrens Clin, Osaka 5440033, Japan
[7] Yagi Pediat Clin, Yao 5810871, Japan
[8] Takasaki Pediat Clin, Fukuoka 8190052, Japan
[9] Shindo Childrens Clin, Fukuoka 8140121, Japan
[10] Yamashita Pediat Clin, Itoshima 8191112, Japan
[11] Yokoyama Childrens Clin, Kasuga, Fukuoka 8160801, Japan
[12] Kiyomatsu Pediat Clin, Fukuoka 8140021, Japan
[13] Osaka City Univ Hosp, Management Bur, Osaka 5458586, Japan
[14] Coll Healthcare Management, Healthcare Management, Miyama 8350018, Japan
[15] SOUSEIKAI, Clin Epidemiol Res Ctr, Fukuoka 8130017, Japan