1 Prevention and Control of Infection Administration, King Saud Medical City, Ministry of Health, P.O. Box 2897, Riyadh 11196, Saudi Arabia.
2 Community Medicine Research Department, National Research Center, 33 El Buhouth Street 12622, Cairo, Egypt.
3 Research and Innovation Center, King Saud Medical City, P.O. Box 2897, Riyadh 11196, Ministry of Health & College of Medicine, Al Faisal University, P.O. Box 50927 Riyadh 11533, Saudi Arabia.
4 Hubert Department of Global Health, Rollins School of Public Health, Emory University, 1518 Clifton Rd, 30322, Atlanta, GA, USA.
5 Division of Infectious Diseases, Kyung Hee University, Seoul 446-701, Korea.