1. Vanderbilt Vaccine Research Program, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee;
2. Fundación INFANT, Buenos Aires, Argentina;
3. Texas Tech University Health Science Center, Lubbock, Texas;
4. Section of Infectious Diseases, Department of Pediatrics, Baylor College of Medicine and Texas Children’s Hospital, Houston, Texas;
5. Blank Children’s Hospital, Des Moines, Iowa; and
6. University of Michigan, Ann Arbor, Michigan