[1] Childrens Hosp, Neuroepidemiol Unit, Dept Neurol, Boston, MA 02115 USA
[2] Harvard Univ, Sch Med, Dept Neurol, Boston, MA 02115 USA
[3] Hannover Med Sch, Perinatal Infect Dis Epidemiol Unit, D-30623 Hannover, Germany
[4] Harvard Univ, Sch Publ Hlth, Dept Biostat, Boston, MA 02115 USA
[5] St Peters Med Ctr, Dept Pathol, New Brunswick, NJ 08903 USA
[6] Univ Med & Dent New Jersey, New Jersey Med Sch, Dept Pathol, Newark, NJ 07103 USA
[7] Brigham & Womens Hosp, Dept Pathol, Boston, MA 02115 USA
[8] Childrens Hosp, Ctr Med, Div Pathol, Cincinnati, OH 45229 USA