1. Infectious Diseases Research Laboratory, Research Division, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 06726, Mexico
2. Department of Paediatrics, Hanoi Medical University, 1,Ton That Tung, Hanoi 116001, Vietnam
3. Department of Gastroenterology, National Children’s Hospital, 18 Lane 879 La Thanh Street, Lang Thuong, Dong Da, Hanoi 116001, Vietnam
4. Department of Paediatrics, University of the Philippines, Philippine General Hospital, Manila 1000, Philippines
5. Sanofi-Aventis, 38 Beach Road, Singapore 189767, Singapore
6. Sanofi, 157 Avenue Charles de Gaulle, 92200 Neuilly-Sur-Seine, France