1. Department of Infectious Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 26 Acad. Georgi Bonchev Str., 1113, Sofia, Bulgaria.
2. Department of Immunobiology of Reproduction, Institute of Biology and Immunology of Reproduction, Bulgarian Academy of Sciences, 73 Tzarigradsko shose, 1113, Sofia, Bulgaria.
3. Department of Animal Diversity and Resources, Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria.
4. Department of Biology and Pathology, National Research Station of Game Management, 1113, Sofia, Bulgaria.
5. Yersinia Research Unit and National Reference Laboratory, Institut Pasteur, 28 rue du Docteur Roux, 75015, Paris, France.
6. Laboratory of Zooanthroponotic Infections, St. Petersburg Pasteur Institute, 14 Mira str., 197101, St. Petersburg, Russia.