[1] Duke Univ, Sch Med, Duke Clin Res Inst, Box 17969, Durham, NC 27715 USA
[2] Seoul Natl Univ, Boramae Hosp, Seoul, South Korea
[3] Seoul Natl Univ, Coll Med, Seoul, South Korea
[4] Univ Virginia Hlth Syst, Div Infect Dis & Int Hlth, Charlottesville, VA USA
[5] Duke Univ, Dept Pediat, Sch Med, Durham, NC 27706 USA
[6] Pediat Obstet Ctr Res & Educ, Sunrise, FL USA
[7] Penn State Coll Med, Dept Pediat, Hershey, PA USA