1. Department of Infection and Immunity, Royal Free London Travel Health and Immunisation Clinic, London, UK
2. Department of Medicine and Diagnostics, Swiss Tropical and Public Health Institute, Basel, Switzerland
3. Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland
4. Department of Clinical Medicine, University of Helsinki, Helsinki, Finland
5. Inflammation Center, Division of Infectious Diseases, Helsinki University Hospital, Helsinki, Finland
6. Unit of Infectious Diseases, Karolinska Institutet, Stockholm, Sweden