[1] Tokyo Metropolitan Childrens Med Ctr, Dept Gen Pediat, Tokyo, Japan
[2] Tokyo Metropolitan Childrens Med Ctr, Dept Pediat, Div Infect Dis, Tokyo, Japan
[3] Tokyo Metropolitan Childrens Med Ctr, Div Orthoped, Tokyo, Japan
[4] Tokyo Metropolitan Childrens Med Ctr, Div Lab, Tokyo, Japan
[5] Toho Univ, Sch Med, Dept Microbiol & Infect Dis, Tokyo, Japan
[6] Harvard Sch Publ Hlth, Dept Quantitat Methods, Boston, MA USA