1. Department of Family Medicine, College of Medicine, Al-Imam Mohammad Ibn Saud Islamic University, Riyadh 11432, Saudi Arabia
2. Department of Infection and Immunity, King Faisal Specialist Hospital & Research Center, Riyadh 11211, Saudi Arabia
3. Department of Microbiology and Immunology, College of Medicine, Alfaisal University, Riyadh 11211, Saudi Arabia