1. Kazan (Volga Region) Federal University, Kremlyovskaya 18, Kazan 420008, Russia
2. Kazan Scientific and Research Institute of Epidemiology and Microbiology, Bolshaya Krasnaya 67, Kazan 420015, Russia
3. I.M. Sechenov First Moscow State Medical University, Trubetskaya 8, Bldg 2, Moscow 119991, Russia