1. Institute of Public Health of Serbia, Serbia, Belgrade
2. Department of Addictology, First Faculty of Medicine, Charles University and General Teaching Hospital in Prague, Czech Republic, Prague
3. Wake Forest School of Medicine, Winston-Salem, NC, USA
4. Perinatal HIV Research Unit, University of the Witwatersrand, Johannesburg, South Africa
5. National Monitoring Centre for drugs and addiction, the Office of the Government of the Czech Republic, Czech Republic, Prague