1. Pham Ngoc Thach Hospital, Ho Chi Minh City, Viet Nam
2. School of Public Health, Université Libre de Bruxelles (ULB), Brussels, Belgium
3. Department of Paediatrics, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Viet Nam
4. Clinic of Immuno-Allergology, Centre Hospitalier Universitaire Brugmann, ULB, Brussels, Belgium