1. Applied Epidemiology, Sabin Vaccine Institute, Washington, DC, USA
2. Stanford University, Stanford, California, USA
3. Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Sher-E-Bangla Nagar, Dhaka, Bangladesh
4. Aga Khan University, Karachi, Pakistan
5. Bangladesh Institute of Child Health, Dhaka Shishu Hospital, Sher-E-Bangla Nagar, Dhaka, Bangladesh
6. Dhulikhel Hospital, Kathmandu University Hospital, Dhulikhel, Nepal
7. Global Immunization Division, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia, USA
8. National Foundation for the Centers for Disease Control and Prevention, Atlanta, Georgia, USA
9. Department of Medicine, Division of Infectious Diseases, University of Toronto, Toronto, Ontario, Canada