1. Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Greece
2. Medical School, University of Cyprus, Nicosia
3. Transmission Reduction Intervention Project, Athens, Greece
4. National Development and Research Institutes, New York, New York
5. Departments of Medicine and Public Health Sciences, University of Chicago Medical Center, Center for AIDS Elimination, Illinois
6. Laikon General Hospital, First Department of Internal Medicine, Medical School, National and Kapodistrian University of Athens, Greece
7. Alliance for Public Health, Kyiv, Ukraine
8. Medical School, National and Kapodistrian University of Athens, Greece