1. Department of Public Health, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland
2. Travel Clinic, University of Zurich, 8001 Zurich, Switzerland
3. Wearable Computing Laboratory, ETH Zurich, Swiss Federal Institute of Technology, Zurich, Switzerland
4. Medical Services and Diagnostic Department, University of Basel, Swiss Tropical and Public Health Institute, Basel, Switzerland
5. Department of Infectious Diseases, Cantonal Hospital, 9007 St. Gallen, Switzerland