1. College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
2. King Abdullah International Medical Research Centre, Ministry of National Guard-Health Affairs, Riyadh, Saudi Arabia
3. Department of Microbiology, Faculty of Sciences and Technology, Al Neelain University, Khartoum, Sudan
4. Department of Basic Medical Sciences, Faculty of Medicine, Jazan University, Jazan, Saudi Arabia