1 Specialty Internal Medicine and Quality Department, Johns Hopkins Aramco Healthcare, Dhahran, Saudi Arabia.
2 Indiana University School of Medicine, Indiana, USA.
3 Johns Hopkins University School of Medicine, Baltimore, MD, USA.
4 Faculty of Medicine, Riga Stradiņš University, Riga, LV-1007, Latvia.
5 Second Department of Dermatology, Colentina Clinical Hospital, Bucharest, Romania.
6 University of Zürich, Institute for Epidemiology, Biostatistics and Prevention, WHO Collaborating Centre for Travellers' Health, Department of Global and Public Health, MilMedBiol Competence Centre, Zürich, Switzerland.