1. Institute of Microbiology and Immunology; Faculty of Medicine University of Belgrade; Belgrade Serbia
2. Clinics for Dermatology; Clinical Centre of Serbia; Belgrade Serbia
3. Dermatology Department; Military Medical Center; Belgrade Serbia
4. Institute of Public Health; Nis Serbia
5. Faculty of Medicine University of Nis; Nis Serbia
6. Institute of Microbiology; School of Dental medicine; University of Belgrade; Belgrade Serbia