1. Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria.
2. Department of Infectious Diseases, Military Medical Academy, Sofia, Bulgaria.
3. Department of Food Quality and Safety and Veterinary Legislation, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria.
4. Department of Biology, Faculty of Nature and Life Sciences, University of El Oued, El Oued, Algeria.
5. Laboratory of Biology, Environment and Health (LBEH), Faculty of Nature and Life Sciences, University of El Oued, El Oued, Algeria.
6. Department of Occupational Medicine, Faculty of Public Health, Medical University, Sofia, Bulgaria.
7. Department of Infectious Pathology, Hygiene, Technology and Control of Foods from Animal Origin, Faculty of Veterinary Medicine, University of Forestry, Sofia, Bulgaria.