1. Department of Pediatrics, Prince Sultan Military Medical City, Al Faisal University, P.O. Box 7897, Riyadh 11159, Saudi Arabia
2. College of Medicine, Al Marifah University, P.O. Box 92882, Riyadh 11663, Saudi Arabia
3. Department of Pediatrics, Prince Sultan Military Medical City, P.O. Box 26523, Riyadh 12841, Saudi Arabia
4. Respiratory Division, Department of Pediatrics, Prince Sultan Military Medical City, P.O. Box 7456, Riyadh 13326, Saudi Arabia
5. Department of Emergency, Prince Sultan Military Medical City, P.O. Box 282236, Riyadh 11392, Saudi Arabia
6. Department of Infectious Disease, Prince Sultan Military Medical City, P.O. Box 106383, Riyadh 11666, Saudi Arabia
7. Department of Pediatrics, Abha Maternity & Children Hospital, P.O. Box 62521, Abha 3613, Saudi Arabia
8. Department of Pediatrics, King Fahd Hospital of the University, P.O. Box 2208, Al-Khobar 31952, Saudi Arabia
9. College of Medicine, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 34212, Saudi Arabia
10. Dr. Soliman Fakeeh Hospital, P.O. Box 2537, Jeddah 21461, Saudi Arabia
11. Department of Pediatrics, Umm Al-Qura University, P.O. Box 715, Mecca 24382, Saudi Arabia