1 Prenatal Pediatrics Institute, Children's National Hospital, Washington, DC 20010, USA.
2 Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC 20052, USA.
3 Department of Neurology, The George Washington University School of Medicine and Health Sciences, Washington, DC 20052, USA.
4 Division of Pediatric Infectious Diseases, Children's National Hospital, Washington, DC 20010, USA.
5 Department of Microbiology, Immunology and Tropical Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC 20052, USA.