1. Intensive Care Department, King Abdulaziz Medical City, Riyadh, Saudi Arabia
2. Department of Respiratory Services, King Abdulaziz Medical City, Riyadh, Saudi Arabia
3. Department of Infectious Diseases, Preventive Medicine Directorate, Ministry of Health, Riyadh, Saudi Arabia
4. College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
5. Department of Hepatobiliary Surgery and Liver Transplantation, King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Riyadh, Saudi Arabia
6. Department of Epidemiology and Biostatistics, College of Medicine, King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Riyadh, Saudi Arabia
7. Department of Medicine, Cooper Medical School of Rowan University, Camden, NJ
8. St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada
9. Section of Critical Care Medicine, Mount Sinai Hospital, University of Toronto, Toronto, ON Canada
10. Moses H. Cone Memorial Hospital, Greensboro, NC
11. Royal Jubilee Hospital/Victoria General Hospital, University of British Columbia, Victoria, BC, Canada
12. Section of Pulmonary Medicine, McGill University, Montreal, QC, Canada
13. Cooper Medical School of Rowan University, Camden, NJ
14. Department of Medical Microbiology and Pharmacology/Therapeutics, Section of Critical Care Medicine and Section of Infectious Diseases, Health Sciences Center and St. Boniface Hospital, University of Manitoba, Winnipeg, MB, Canada
15. Division of Cardiovascular Diseases and Critical Care Medicine, Cooper Medical School of Rowan University, Camden, NJ