1. University College London; London; UK
2. Copenhagen HIV Programme; University of Copenhagen; Copenhagen; Denmark
3. Hospital Carlos III; Madrid; Spain
4. Medical University; Wroclaw; Poland
5. Regional AIDS Centre; Svetlogorsk; Belarus
6. San Raffaele Hospital; Milan; Italy
7. Division of Infectious Diseases and Hospital Epidemiology; University Hospital Zurich; University of Zurich; Zurich; Switzerland
8. University of Bonn; Bonn; Germany