1. Department for Acquired Immune Deficiency , “Prof. Iv. Kirov” Specialized Hosptal for Active Treatment of Infectious and Parasitic Diseases, Department of Infectious Diseases, Parasitology and Tropical Medicine , Medical University – Sofia , Bulgaria
2. National Laboratory of Immunology , National Center for Infectious and Parasitic Diseases – Sofia , Bulgaria
3. National HIV Reference Laboratory, National Center for Infectious and Parasitic Diseases – Sofia , Bulgaria
4. National Laboratory of Parasitology, National Center for Infectious and Parasitic Diseases – Sofia , Bulgaria