1. College of Medicine, University of the Philippines, Manila 1000, Philippines.
2. Section of Allergy and Immunology, Department of Internal Medicine, Philippine General Hospital, Manila 1000, Philippines.
3. De La Salle Health Sciences Institute, College of Medicine, Dasmariñas City 4114, Philippines.
4. Section of Allergy and Immunology, Department of Pediatrics, Dr. Fe Del Mundo Medical Center, Quezon City, Metro Manila 1100, Philippines.
5. Department of Pediatrics, Chinese General Hospital, Manila 1014, Philippines.
6. Department of Pediatrics, College of Medicine, Manila Central University FDTMF, Caloocan City, Metro Manila 1400, Philippines.
7. Department of Pediatrics, Manila Doctors Hospital, Manila 1000, Philippines.